diff --git a/xml/constraints-3.10.rng b/xml/constraints-3.10.rng
index bc3c7c3b3f..5fbb7ac124 100644
--- a/xml/constraints-3.10.rng
+++ b/xml/constraints-3.10.rng
@@ -1,273 +1,287 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <grammar xmlns="http://relaxng.org/ns/structure/1.0"
          datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
   <start>
       <ref name="element-constraints"/>
   </start>
 
   <define name="element-constraints">
     <element name="constraints">
       <zeroOrMore>
         <choice>
           <ref name="element-location"/>
           <ref name="element-colocation"/>
           <ref name="element-order"/>
           <ref name="element-rsc_ticket"/>
         </choice>
       </zeroOrMore>
     </element>
   </define>
 
   <define name="element-location">
     <element name="rsc_location">
       <attribute name="id"><data type="ID"/></attribute>
       <choice>
         <group>
           <choice>
             <attribute name="rsc"><data type="IDREF"/></attribute>
             <attribute name="rsc-pattern"><text/></attribute>
           </choice>
           <optional>
             <attribute name="role">
               <ref name="attribute-roles"/>
             </attribute>
           </optional>
         </group>
         <oneOrMore>
           <ref name="element-resource-set"/>
         </oneOrMore>
       </choice>
       <choice>
         <group>
           <externalRef href="score.rng"/>
           <attribute name="node"><text/></attribute>
         </group>
+        <!--
+         @COMPAT: When we can break backward compatibility, limit this to a
+         single rule
+         -->
         <oneOrMore>
           <grammar>
             <include href="rule-3.10.rng">
               <start>
                 <ref name="element-rule-location"/>
               </start>
             </include>
           </grammar>
         </oneOrMore>
       </choice>
+
+      <!-- @COMPAT: The lifetime element is deprecated -->
       <optional>
         <ref name="element-lifetime"/>
       </optional>
+
       <optional>
         <attribute name="resource-discovery">
           <ref name="attribute-discovery"/>
         </attribute>
       </optional>
     </element>
   </define>
 
   <define name="element-resource-set">
     <element name="resource_set">
       <choice>
         <attribute name="id-ref"><data type="IDREF"/></attribute>
         <group>
           <attribute name="id"><data type="ID"/></attribute>
           <optional>
             <attribute name="sequential"><data type="boolean"/></attribute>
           </optional>
           <optional>
             <attribute name="require-all"><data type="boolean"/></attribute>
           </optional>
           <optional>
             <attribute name="ordering">
               <choice>
                 <value>group</value>
                 <value>listed</value>
               </choice>
             </attribute>
           </optional>
           <optional>
             <attribute name="action">
               <ref name="attribute-actions"/>
             </attribute>
           </optional>
           <optional>
             <attribute name="role">
               <ref name="attribute-roles"/>
             </attribute>
           </optional>
           <optional>
             <choice>
               <externalRef href="score.rng"/>
               <attribute name="kind">
                 <ref name="order-types"/>
               </attribute>
              </choice>
           </optional>
           <oneOrMore>
             <element name="resource_ref">
               <attribute name="id"><data type="IDREF"/></attribute>
             </element>
           </oneOrMore>
         </group>
       </choice>
     </element>
   </define>
 
   <define name="element-colocation">
     <element name="rsc_colocation">
       <attribute name="id"><data type="ID"/></attribute>
       <optional>
         <externalRef href="score.rng"/>
       </optional>
       <optional>
         <attribute name="influence"><text/></attribute>
       </optional>
+
+      <!-- @COMPAT: The lifetime element is deprecated -->
       <optional>
         <ref name="element-lifetime"/>
       </optional>
+
       <choice>
         <oneOrMore>
           <ref name="element-resource-set"/>
         </oneOrMore>
         <group>
           <attribute name="rsc"><data type="IDREF"/></attribute>
           <attribute name="with-rsc"><data type="IDREF"/></attribute>
           <optional>
             <attribute name="node-attribute"><text/></attribute>
           </optional>
           <optional>
             <attribute name="rsc-role">
               <ref name="attribute-roles"/>
             </attribute>
           </optional>
           <optional>
             <attribute name="with-rsc-role">
               <ref name="attribute-roles"/>
             </attribute>
           </optional>
         </group>
       </choice>
     </element>
   </define>
 
   <define name="element-order">
     <element name="rsc_order">
       <attribute name="id"><data type="ID"/></attribute>
+
+      <!-- @COMPAT: The lifetime element is deprecated -->
       <optional>
         <ref name="element-lifetime"/>
       </optional>
+
       <optional>
         <attribute name="symmetrical"><data type="boolean"/></attribute>
       </optional>
       <optional>
         <attribute name="require-all"><data type="boolean"/></attribute>
       </optional>
       <optional>
         <choice>
           <externalRef href="score.rng"/>
           <attribute name="kind">
             <ref name="order-types"/>
           </attribute>
         </choice>
       </optional>
       <choice>
         <oneOrMore>
           <ref name="element-resource-set"/>
         </oneOrMore>
         <group>
           <attribute name="first"><data type="IDREF"/></attribute>
           <attribute name="then"><data type="IDREF"/></attribute>
           <optional>
             <attribute name="first-action">
               <ref name="attribute-actions"/>
             </attribute>
           </optional>
           <optional>
             <attribute name="then-action">
               <ref name="attribute-actions"/>
             </attribute>
           </optional>
         </group>
       </choice>
     </element>
   </define>
 
   <define name="element-rsc_ticket">
     <element name="rsc_ticket">
       <attribute name="id"><data type="ID"/></attribute>
       <choice>
         <oneOrMore>
           <ref name="element-resource-set"/>
         </oneOrMore>
         <group>
           <attribute name="rsc"><data type="IDREF"/></attribute>
           <optional>
             <attribute name="rsc-role">
               <ref name="attribute-roles"/>
             </attribute>
           </optional>
         </group>
       </choice>
       <attribute name="ticket"><text/></attribute>
       <optional>
         <attribute name="loss-policy">
           <choice>
             <value>stop</value>
             <value>demote</value>
             <value>fence</value>
             <value>freeze</value>
           </choice>
         </attribute>
       </optional>
     </element>
   </define>
 
   <define name="attribute-discovery">
     <choice>
       <value>always</value>
       <value>never</value>
       <value>exclusive</value>
     </choice>
   </define>
 
   <define name="attribute-actions">
     <choice>
       <value>start</value>
       <value>promote</value>
       <value>demote</value>
       <value>stop</value>
     </choice>
   </define>
 
   <define name="attribute-roles">
     <choice>
       <value>Stopped</value>
       <value>Started</value>
       <value>Promoted</value>
       <value>Unpromoted</value>
       <value>Master</value>
       <value>Slave</value>
     </choice>
   </define>
 
   <define name="order-types">
     <choice>
       <value>Optional</value>
       <value>Mandatory</value>
       <value>Serialize</value>
     </choice>
   </define>
 
+  <!-- @COMPAT: The lifetime element is deprecated -->
   <define name="element-lifetime">
     <element name="lifetime">
       <oneOrMore>
         <grammar>
           <include href="rule-3.10.rng">
             <start>
               <ref name="element-rule-location"/>
             </start>
           </include>
         </grammar>
       </oneOrMore>
     </element>
   </define>
 
 </grammar>
diff --git a/xml/nvset-3.10.rng b/xml/nvset-3.10.rng
index a29b3a0e69..07565d8fd0 100644
--- a/xml/nvset-3.10.rng
+++ b/xml/nvset-3.10.rng
@@ -1,68 +1,68 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!-- just as nvset-2.9.rng, but allows for instantiated @name restrictions -->
 <grammar xmlns="http://relaxng.org/ns/structure/1.0"
          datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
   <start>
     <ref name="element-nvset"/>
   </start>
 
   <!-- nvpair/@name:
        * generic string by default, parent grammar may want to prohibit
          enumerated names -->
   <define name="element-nvset.name">
     <attribute name="name">
       <text/>
     </attribute>
   </define>
 
   <!-- nvpair/@name:
        * defer element-nvset.name grammar item
        nvpair/@value:
        generic string by default, parent grammar may want to restrict
        enumerated pairs (i.e. related to @name) at once -->
   <define name="element-nvset.name-value">
     <ref name="element-nvset.name"/>
     <optional>
       <attribute name="value"><text/></attribute>
     </optional>
   </define>
 
   <!-- Allow easy redefinition in parent grammars -->
   <define name="element-nvset.rule">
     <externalRef href="rule-3.10.rng"/>
   </define>
 
   <define name="element-nvset">
    <choice>
    <attribute name="id-ref"><data type="IDREF"/></attribute>
    <group>
     <attribute name="id"><data type="ID"/></attribute>
     <interleave>
       <optional>
         <ref name="element-nvset.rule"/>
       </optional>
-        <zeroOrMore>
-          <element name="nvpair">
-            <choice>
-              <group>
-                <attribute name="id-ref"><data type="IDREF"/></attribute>
-                <optional>
-                  <attribute name="name"><text/></attribute>
-                </optional>
-              </group>
-              <group>
-                <attribute name="id"><data type="ID"/></attribute>
-                <ref name="element-nvset.name-value"/>
-              </group>
-            </choice>
-          </element>
-        </zeroOrMore>
+      <zeroOrMore>
+        <element name="nvpair">
+          <choice>
+            <group>
+              <attribute name="id-ref"><data type="IDREF"/></attribute>
+              <optional>
+                <attribute name="name"><text/></attribute>
+              </optional>
+            </group>
+            <group>
+              <attribute name="id"><data type="ID"/></attribute>
+              <ref name="element-nvset.name-value"/>
+            </group>
+          </choice>
+        </element>
+      </zeroOrMore>
       <optional>
         <externalRef href="score.rng"/>
       </optional>
     </interleave>
    </group>
    </choice>
   </define>
 
 </grammar>
diff --git a/xml/resources-3.10.rng b/xml/resources-3.10.rng
index a17f4b47c7..fd213f4384 100644
--- a/xml/resources-3.10.rng
+++ b/xml/resources-3.10.rng
@@ -1,428 +1,457 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <grammar xmlns="http://relaxng.org/ns/structure/1.0"
          datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
   <start>
     <ref name="element-resources"/>
   </start>
 
+  <!--
+   Include rule definitions so that we can override element-nvset.rule based on
+   context
+   -->
+  <include href="rule-3.10.rng">
+    <start combine="choice">
+      <notAllowed/>
+    </start>
+  </include>
+
   <define name="element-resources">
     <element name="resources">
       <zeroOrMore>
         <choice>
           <ref name="element-primitive"/>
           <ref name="element-template"/>
           <ref name="element-group"/>
           <ref name="element-clone"/>
           <ref name="element-master"/>
           <ref name="element-bundle"/>
         </choice>
       </zeroOrMore>
     </element>
   </define>
 
   <!--
    see upgrade-2.10.xsl
    - cibtr:table for="resource-meta-attributes"
    -->
   <define name="primitive-template.meta_attributes.nvpair.name-unsupported">
     <attribute name="name">
       <data type="string">
         <except>
           <choice>
             <value>isolation</value>
             <value>isolation-host</value>
             <value>isolation-instance</value>
             <value>isolation-wrapper</value>
           </choice>
         </except>
       </data>
     </attribute>
   </define>
 
   <define name="element-resource-extra.primitive-template">
     <zeroOrMore>
       <choice>
         <element name="meta_attributes">
           <grammar>
             <include href="nvset-3.10.rng">
               <define name="element-nvset.name">
                 <parentRef name="primitive-template.meta_attributes.nvpair.name-unsupported"/>
               </define>
             </include>
           </grammar>
         </element>
         <element name="instance_attributes">
+          <grammar>
+            <include href="nvset-3.10.rng">
+              <define name="element-nvset.rule">
+                <parentRef name="element-rule-node-allowed"/>
+              </define>
+            </include>
+          </grammar>
+        </element>
+        <element name="utilization">
           <externalRef href="nvset-3.10.rng"/>
         </element>
       </choice>
     </zeroOrMore>
   </define>
 
   <define name="element-primitive">
     <element name="primitive">
       <interleave>
         <attribute name="id"><data type="ID"/></attribute>
         <choice>
           <group>
             <ref name="element-resource-class"/>
             <attribute name="type"><text/></attribute>
           </group>
           <attribute name="template"><data type="IDREF"/></attribute>
         </choice>
         <optional>
           <attribute name="description"><text/></attribute>
         </optional>
         <ref name="element-resource-extra.primitive-template"/>
         <ref name="element-operations"/>
-        <zeroOrMore>
-          <element name="utilization">
-            <externalRef href="nvset-3.10.rng"/>
-          </element>
-        </zeroOrMore>
       </interleave>
     </element>
   </define>
 
   <define name="element-template">
     <element name="template">
       <interleave>
         <attribute name="id"><data type="ID"/></attribute>
         <ref name="element-resource-class"/>
         <attribute name="type"><text/></attribute>
         <optional>
           <attribute name="description"><text/></attribute>
         </optional>
         <ref name="element-resource-extra.primitive-template"/>
         <ref name="element-operations"/>
-        <zeroOrMore>
-          <element name="utilization">
-            <externalRef href="nvset-3.10.rng"/>
-          </element>
-        </zeroOrMore>
       </interleave>
     </element>
   </define>
 
   <define name="element-bundle">
     <element name="bundle">
       <interleave>
         <attribute name="id"><data type="ID"/></attribute>
         <optional>
           <attribute name="description"><text/></attribute>
         </optional>
         <ref name="element-resource-extra"/>
         <choice>
           <element name="docker">
             <attribute name="image"><text/></attribute>
             <optional>
               <attribute name="replicas"><data type="integer"/></attribute>
             </optional>
             <optional>
               <attribute name="replicas-per-host"><data type="integer"/></attribute>
             </optional>
             <optional>
               <choice>
                 <attribute name="masters"><data type="integer"/></attribute>
                 <attribute name="promoted-max"><data type="integer"/></attribute>
               </choice>
             </optional>
             <optional>
               <attribute name="run-command"> <text/></attribute>
             </optional>
             <optional>
               <attribute name="network"><text/></attribute>
             </optional>
             <optional>
               <attribute name="options"><text/></attribute>
             </optional>
           </element>
           <element name="rkt">
             <attribute name="image"><text/></attribute>
             <optional>
               <attribute name="replicas"><data type="integer"/></attribute>
             </optional>
             <optional>
               <attribute name="replicas-per-host"><data type="integer"/></attribute>
             </optional>
             <optional>
               <choice>
                 <attribute name="masters"><data type="integer"/></attribute>
                 <attribute name="promoted-max"><data type="integer"/></attribute>
               </choice>
             </optional>
             <optional>
               <attribute name="run-command"> <text/></attribute>
             </optional>
             <optional>
               <attribute name="network"><text/></attribute>
             </optional>
             <optional>
               <attribute name="options"><text/></attribute>
             </optional>
           </element>
           <element name="podman">
             <attribute name="image"><text/></attribute>
             <optional>
               <attribute name="replicas"><data type="integer"/></attribute>
             </optional>
             <optional>
               <attribute name="replicas-per-host"><data type="integer"/></attribute>
             </optional>
             <optional>
               <choice>
                 <attribute name="masters"><data type="integer"/></attribute>
                 <attribute name="promoted-max"><data type="integer"/></attribute>
               </choice>
             </optional>
             <optional>
               <attribute name="run-command"> <text/></attribute>
             </optional>
             <optional>
               <attribute name="network"><text/></attribute>
             </optional>
             <optional>
               <attribute name="options"><text/></attribute>
             </optional>
           </element>
         </choice>
         <optional>
           <element name="network">
             <optional>
               <attribute name="ip-range-start"><text/></attribute>
             </optional>
             <optional>
               <attribute name="control-port"><data type="integer"/></attribute>
             </optional>
             <optional>
               <attribute name="host-interface"><text/></attribute>
             </optional>
             <optional>
               <attribute name="host-netmask"><data type="integer"/></attribute>
             </optional>
             <optional>
               <attribute name="add-host"><data type="boolean"/></attribute>
             </optional>
             <zeroOrMore>
               <element name="port-mapping">
                 <attribute name="id"><data type="ID"/></attribute>
                 <choice>
                   <group>
                     <attribute name="port"><data type="integer"/></attribute>
                     <optional>
                       <attribute name="internal-port"><data type="integer"/></attribute>
                     </optional>
                   </group>
                   <attribute name="range">
                     <data type="string">
                       <param name="pattern">([0-9\-]+)</param>
                     </data>
                   </attribute>
                 </choice>
               </element>
             </zeroOrMore>
           </element>
         </optional>
         <optional>
           <element name="storage">
             <zeroOrMore>
               <element name="storage-mapping">
                 <attribute name="id"><data type="ID"/></attribute>
                 <choice>
                   <attribute name="source-dir"><text/></attribute>
                   <attribute name="source-dir-root"><text/></attribute>
                 </choice>
                 <attribute name="target-dir"><text/></attribute>
                 <optional>
                   <attribute name="options"><text/></attribute>
                 </optional>
               </element>
             </zeroOrMore>
           </element>
         </optional>
         <optional>
           <ref name="element-primitive"/>
         </optional>
       </interleave>
     </element>
   </define>
 
   <define name="element-group">
     <element name="group">
       <attribute name="id"><data type="ID"/></attribute>
       <optional>
         <attribute name="description"><text/></attribute>
       </optional>
       <interleave>
         <ref name="element-resource-extra"/>
         <oneOrMore>
           <ref name="element-primitive"/>
         </oneOrMore>
       </interleave>
     </element>
   </define>
 
   <define name="element-clone">
     <element name="clone">
       <attribute name="id"><data type="ID"/></attribute>
       <optional>
         <attribute name="description"><text/></attribute>
       </optional>
       <interleave>
         <ref name="element-resource-extra"/>
         <choice>
           <ref name="element-primitive"/>
           <ref name="element-group"/>
         </choice>
       </interleave>
     </element>
   </define>
 
   <define name="element-master">
     <element name="master">
       <attribute name="id"><data type="ID"/></attribute>
       <optional>
         <attribute name="description"><text/></attribute>
       </optional>
       <interleave>
         <ref name="element-resource-extra"/>
         <choice>
           <ref name="element-primitive"/>
           <ref name="element-group"/>
         </choice>
       </interleave>
     </element>
   </define>
 
   <define name="element-resource-extra">
     <zeroOrMore>
       <choice>
         <element name="meta_attributes">
           <externalRef href="nvset-3.10.rng"/>
         </element>
         <element name="instance_attributes">
-          <externalRef href="nvset-3.10.rng"/>
+          <grammar>
+            <include href="nvset-3.10.rng">
+              <define name="element-nvset.rule">
+                <parentRef name="element-rule-node-allowed"/>
+              </define>
+            </include>
+          </grammar>
         </element>
       </choice>
     </zeroOrMore>
   </define>
 
   <!--
    see upgrade-2.10.xsl
    - cibtr:table for="resources-operation"
    -->
   <define name="op.meta_attributes.nvpair.name-unsupported">
     <attribute name="name">
       <data type="string">
         <except>
           <choice>
             <value>requires</value>
           </choice>
         </except>
       </data>
     </attribute>
   </define>
 
   <define name="element-resource-extra.op">
     <zeroOrMore>
       <choice>
         <element name="meta_attributes">
           <grammar>
             <include href="nvset-3.10.rng">
               <define name="element-nvset.name">
                 <parentRef name="op.meta_attributes.nvpair.name-unsupported"/>
               </define>
+
+              <!--
+               @COMPAT: Support for node attribute expressions is deprecated
+               here. We can just delete this define when we drop support.
+              -->
+              <define name="element-nvset.rule">
+                <parentRef name="element-rule-node-allowed"/>
+              </define>
             </include>
           </grammar>
         </element>
         <element name="instance_attributes">
-          <externalRef href="nvset-3.10.rng"/>
+          <grammar>
+            <include href="nvset-3.10.rng">
+              <define name="element-nvset.rule">
+                <parentRef name="element-rule-node-allowed"/>
+              </define>
+            </include>
+          </grammar>
         </element>
       </choice>
     </zeroOrMore>
   </define>
 
   <define name="element-operations">
     <optional>
       <element name="operations">
         <optional>
           <attribute name="id"><data type="ID"/></attribute>
         </optional>
         <optional>
           <attribute name="id-ref"><data type="IDREF"/></attribute>
         </optional>
         <zeroOrMore>
           <element name="op">
             <attribute name="id"><data type="ID"/></attribute>
             <attribute name="name"><text/></attribute>
             <attribute name="interval"><text/></attribute>
             <optional>
               <attribute name="description"><text/></attribute>
             </optional>
             <optional>
               <choice>
                 <attribute name="start-delay"><text/></attribute>
                 <attribute name="interval-origin"><text/></attribute>
               </choice>
             </optional>
             <optional>
               <attribute name="timeout"><text/></attribute>
             </optional>
             <optional>
               <attribute name="enabled"><data type="boolean"/></attribute>
             </optional>
             <optional>
               <attribute name="record-pending"><data type="boolean"/></attribute>
             </optional>
             <optional>
               <attribute name="role">
                 <choice>
                   <value>Stopped</value>
                   <value>Started</value>
                   <value>Promoted</value>
                   <value>Unpromoted</value>
                   <value>Slave</value>
                   <value>Master</value>
                 </choice>
               </attribute>
             </optional>
             <optional>
               <attribute name="on-fail">
                 <choice>
                   <value>ignore</value>
                   <value>block</value>
                   <value>demote</value>
                   <value>stop</value>
                   <value>restart</value>
                   <value>standby</value>
                   <value>fence</value>
                   <value>restart-container</value>
                 </choice>
               </attribute>
             </optional>
             <ref name="element-resource-extra.op"/>
           </element>
         </zeroOrMore>
       </element>
     </optional>
   </define>
 
   <define name="element-resource-class">
     <choice>
       <group>
         <attribute name="class"><value>ocf</value></attribute>
         <attribute name="provider"><text/></attribute>
       </group>
       <attribute name="class">
         <choice>
           <value>lsb</value>
           <value>heartbeat</value>
           <value>stonith</value>
           <value>upstart</value>
           <value>service</value>
           <value>systemd</value>
           <value>nagios</value>
         </choice>
       </attribute>
     </choice>
   </define>
 </grammar>
diff --git a/xml/rule-3.10.rng b/xml/rule-3.10.rng
index 59b482a676..6ef362f58a 100644
--- a/xml/rule-3.10.rng
+++ b/xml/rule-3.10.rng
@@ -1,382 +1,433 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <grammar xmlns="http://relaxng.org/ns/structure/1.0"
          xmlns:ann="http://relaxng.org/ns/compatibility/annotations/1.0"
          datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
   <start>
       <ref name="element-rule"/>
   </start>
 
   <!--
+   Rule elements allow different syntax depending on their context, each of
+   which gets their own rule definition below:
+
+   1. rsc_location
+   2. meta_attributes within rsc_defaults
+   3. meta_attributes within op_defaults
+   4. all other contexts that allow node attribute expressions
+      (instance_attributes elements within bundle, clone, group, op, primitive,
+      and template elements; and meta_attributes elements within op elements)
+   5. all other contexts (cluster_property_set elements; instance_attributes
+      within alert, node, and recipient elements; meta_attributes within alert,
+      bundle, clone, group, primitive, recipient, and template elements; and
+      utilization elements within node, primitive, and template elements)
+
    The COMPAT comments below mark items that are invalid in their given context
    and should be removed at a compatibility break.
    -->
 
-  <!--
-   A rule element that doesn't match any of the special cases defined below
-   -->
-  <define name="element-rule">
+  <!-- 1. rule element within rsc_location -->
+  <define name="element-rule-location">
     <element name="rule">
       <choice>
         <attribute name="id-ref"><data type="IDREF"/></attribute>
         <group>
           <ref name="rule-common"/>
           <oneOrMore>
             <choice>
-              <ref name="expression"/>
+              <ref name="expression-location"/>
               <ref name="date_expression"/>
-              <ref name="element-rule"/>
+              <ref name="element-rule-location"/>
 
-              <!--
-               @COMPAT: The below expression types are invalid for element-rule
-               -->
+              <!-- @COMPAT: The below expression types are invalid here -->
               <ref name="rsc_expression"/>
               <ref name="op_expression"/>
             </choice>
           </oneOrMore>
-
-          <!--
-           @COMPAT: The below score attributes are invalid for element-rule
-           -->
           <optional>
             <choice>
               <externalRef href="score.rng"/>
               <attribute name="score-attribute"><text/></attribute>
             </choice>
           </optional>
         </group>
       </choice>
     </element>
   </define>
 
-  <!-- A rule element in a location constraint -->
-  <define name="element-rule-location">
+  <!-- 2. rule element within rsc_defaults -->
+  <define name="element-rule-rsc_defaults">
     <element name="rule">
       <choice>
         <attribute name="id-ref"><data type="IDREF"/></attribute>
         <group>
           <ref name="rule-common"/>
           <oneOrMore>
             <choice>
-              <ref name="expression-location"/>
               <ref name="date_expression"/>
-              <ref name="element-rule-location"/>
+              <ref name="rsc_expression"/>
+              <ref name="element-rule-rsc_defaults"/>
 
-              <!--
-               @COMPAT: The below expression types are invalid for
-               element-rule-location
-               -->
+              <!-- @COMPAT: The below expression type is deprecated here -->
+              <ref name="expression"/>
+
+              <!-- @COMPAT: The below expression type is invalid here -->
+              <ref name="op_expression"/>
+            </choice>
+          </oneOrMore>
+
+          <!-- @COMPAT: The below score attributes are invalid here -->
+          <optional>
+            <choice>
+              <externalRef href="score.rng"/>
+              <attribute name="score-attribute"><text/></attribute>
+            </choice>
+          </optional>
+        </group>
+      </choice>
+    </element>
+  </define>
+
+  <!-- 3. rule element within op_defaults -->
+  <define name="element-rule-op_defaults">
+    <element name="rule">
+      <choice>
+        <attribute name="id-ref"><data type="IDREF"/></attribute>
+        <group>
+          <ref name="rule-common"/>
+          <oneOrMore>
+            <choice>
+              <ref name="date_expression"/>
               <ref name="rsc_expression"/>
               <ref name="op_expression"/>
+              <ref name="element-rule-op_defaults"/>
+
+              <!-- @COMPAT: The below expression type is deprecated here -->
+              <ref name="expression"/>
             </choice>
           </oneOrMore>
+
+          <!-- @COMPAT: The below score attributes are invalid here -->
           <optional>
             <choice>
               <externalRef href="score.rng"/>
               <attribute name="score-attribute"><text/></attribute>
             </choice>
           </optional>
         </group>
       </choice>
     </element>
   </define>
 
-  <!-- A rule element in a rsc_defaults element -->
-  <define name="element-rule-rsc_defaults">
+   
+  <!-- 4. rule element in other contexts allowing node attribute expressions -->
+  <define name="element-rule-node-allowed">
     <element name="rule">
       <choice>
         <attribute name="id-ref"><data type="IDREF"/></attribute>
         <group>
           <ref name="rule-common"/>
           <oneOrMore>
             <choice>
               <ref name="expression"/>
               <ref name="date_expression"/>
-              <ref name="rsc_expression"/>
-              <ref name="element-rule-rsc_defaults"/>
+              <ref name="element-rule-node-allowed"/>
 
-              <!--
-               @COMPAT: The below expression type is invalid for
-               element-rule-rsc_defaults
-               -->
+              <!-- @COMPAT: The below expression types are invalid here -->
+              <ref name="rsc_expression"/>
               <ref name="op_expression"/>
             </choice>
           </oneOrMore>
 
-          <!--
-           @COMPAT: The below score attributes are invalid for
-           element-rule-rsc_defaults
-           -->
+          <!-- @COMPAT: The below score attributes are invalid here -->
           <optional>
             <choice>
               <externalRef href="score.rng"/>
               <attribute name="score-attribute"><text/></attribute>
             </choice>
           </optional>
         </group>
       </choice>
     </element>
   </define>
 
-  <!-- A rule element in an op_defaults element -->
-  <define name="element-rule-op_defaults">
+  <!-- 5. rule element within all other contexts -->
+  <define name="element-rule">
     <element name="rule">
       <choice>
         <attribute name="id-ref"><data type="IDREF"/></attribute>
         <group>
           <ref name="rule-common"/>
           <oneOrMore>
             <choice>
-              <ref name="expression"/>
               <ref name="date_expression"/>
+              <ref name="element-rule"/>
+
+              <!-- @COMPAT: The below expression types are invalid here -->
+              <ref name="expression"/>
               <ref name="rsc_expression"/>
               <ref name="op_expression"/>
-              <ref name="element-rule-op_defaults"/>
             </choice>
           </oneOrMore>
 
-          <!--
-           @COMPAT: The below score attributes are invalid for
-           element-rule-op_defaults
-           -->
+          <!-- @COMPAT: The below score attributes are invalid here -->
           <optional>
             <choice>
               <externalRef href="score.rng"/>
               <attribute name="score-attribute"><text/></attribute>
             </choice>
           </optional>
         </group>
       </choice>
     </element>
   </define>
 
   <!-- Attributes that are common to all rule elements -->
   <define name="rule-common">
     <attribute name="id"><data type="ID"/></attribute>
     <optional>
       <attribute name="boolean-op">
         <choice>
           <value>or</value>
           <value>and</value>
         </choice>
       </attribute>
     </optional>
+
+    <!--
+     @COMPAT Role applies only to rules within location constraints. When we can
+     break behavioral backward compatibility, move this to
+     rule-element-location.
+     -->
     <optional>
       <attribute name="role"><text/></attribute>
     </optional>
   </define>
 
   <!-- A node attribute expression -->
   <define name="expression">
     <element name="expression">
       <ref name="expression-common"/>
 
-      <!--
-       @COMPAT: The value-source attribute is invalid for expression
-       -->
       <optional>
         <attribute name="value-source" ann:defaultValue="literal">
           <choice>
             <value>literal</value>
+            <!-- @COMPAT: These value-source choices are invalid here -->
             <value>param</value>
             <value>meta</value>
           </choice>
         </attribute>
       </optional>
     </element>
   </define>
 
   <!-- A node attribute expression in a location constraint -->
   <define name="expression-location">
     <element name="expression">
       <ref name="expression-common"/>
       <optional>
         <attribute name="value-source" ann:defaultValue="literal">
           <choice>
             <value>literal</value>
             <value>param</value>
             <value>meta</value>
           </choice>
         </attribute>
       </optional>
     </element>
   </define>
 
   <!-- Attributes that are common to all <expression> elements -->
   <define name="expression-common">
     <attribute name="id"><data type="ID"/></attribute>
     <attribute name="attribute"><text/></attribute>
-    <attribute name="operation">
-      <choice>
-        <value>lt</value>
-        <value>gt</value>
-        <value>lte</value>
-        <value>gte</value>
-        <value>eq</value>
-        <value>ne</value>
-        <value>defined</value>
-        <value>not_defined</value>
-      </choice>
-    </attribute>
-    <optional>
-      <attribute name="value"><text/></attribute>
-    </optional>
+    <choice>
+      <group>
+        <attribute name="operation">
+          <choice>
+            <value>defined</value>
+            <value>not_defined</value>
+          </choice>
+        </attribute>
+        <!-- @COMPAT value attribute should be prohibited here -->
+        <optional>
+          <attribute name="value"><text/></attribute>
+        </optional>
+      </group>
+      <group>
+        <attribute name="operation">
+          <choice>
+            <value>lt</value>
+            <value>gt</value>
+            <value>lte</value>
+            <value>gte</value>
+            <value>eq</value>
+            <value>ne</value>
+          </choice>
+        </attribute>
+        <!-- @COMPAT value attribute should be required here -->
+        <optional>
+          <attribute name="value"><text/></attribute>
+        </optional>
+      </group>
+    </choice>
     <optional>
       <attribute name="type" ann:defaultValue="string">
         <choice>
           <value>string</value>
           <value>integer</value>
           <value>number</value>
           <value>version</value>
         </choice>
       </attribute>
     </optional>
   </define>
 
   <define name="date_expression">
     <element name="date_expression">
       <attribute name="id"><data type="ID"/></attribute>
       <choice>
         <group>
           <attribute name="operation"><value>in_range</value></attribute>
           <choice>
             <attribute name="start"><text/></attribute>
             <attribute name="end"><text/></attribute>
             <group>
               <attribute name="start"><text/></attribute>
               <attribute name="end"><text/></attribute>
             </group>
           </choice>
           <optional>
             <ref name="duration"/>
           </optional>
         </group>
         <group>
           <attribute name="operation"><value>gt</value></attribute>
           <attribute name="start"><text/></attribute>
         </group>
         <group>
           <attribute name="operation"><value>lt</value></attribute>
           <attribute name="end"><text/></attribute>
         </group>
         <group>
           <attribute name="operation"><value>date_spec</value></attribute>
           <ref name="date_spec"/>
         </group>
       </choice>
     </element>
   </define>
 
   <define name="rsc_expression">
     <element name="rsc_expression">
       <attribute name="id"><data type="ID"/></attribute>
       <optional>
         <attribute name="class"><text/></attribute>
       </optional>
       <optional>
         <attribute name="provider"><text/></attribute>
       </optional>
       <optional>
         <attribute name="type"><text/></attribute>
       </optional>
     </element>
   </define>
 
   <define name="op_expression">
     <element name="op_expression">
       <attribute name="id"><data type="ID"/></attribute>
       <attribute name="name"><text/></attribute>
       <optional>
         <attribute name="interval"><text/></attribute>
       </optional>
     </element>
   </define>
 
   <define name="duration">
     <element name="duration">
       <attribute name="id"><data type="ID"/></attribute>
       <optional>
         <attribute name="years"><text/></attribute>
       </optional>
       <optional>
         <attribute name="months"><text/></attribute>
       </optional>
       <optional>
         <attribute name="weeks"><text/></attribute>
       </optional>
       <optional>
         <attribute name="days"><text/></attribute>
       </optional>
       <optional>
         <attribute name="hours"><text/></attribute>
       </optional>
       <optional>
         <attribute name="minutes"><text/></attribute>
       </optional>
       <optional>
         <attribute name="seconds"><text/></attribute>
       </optional>
 
-      <!-- @COMPAT: The below attributes are invalid for duration -->
+      <!-- @COMPAT: The below attributes are invalid here -->
       <optional>
         <attribute name="monthdays"><text/></attribute>
       </optional>
       <optional>
         <attribute name="weekdays"><text/></attribute>
       </optional>
       <optional>
         <attribute name="yearsdays"><text/></attribute>
       </optional>
       <optional>
         <attribute name="weekyears"><text/></attribute>
       </optional>
       <optional>
         <attribute name="moon"><text/></attribute>
       </optional>
     </element>
   </define>
 
   <define name="date_spec">
     <element name="date_spec">
       <attribute name="id"><data type="ID"/></attribute>
       <optional>
         <attribute name="years"><text/></attribute>
       </optional>
       <optional>
         <attribute name="months"><text/></attribute>
       </optional>
       <optional>
         <attribute name="monthdays"><text/></attribute>
       </optional>
       <optional>
         <attribute name="hours"><text/></attribute>
       </optional>
       <optional>
         <attribute name="minutes"><text/></attribute>
       </optional>
       <optional>
         <attribute name="seconds"><text/></attribute>
       </optional>
       <optional>
         <attribute name="yeardays"><text/></attribute>
       </optional>
       <optional>
         <attribute name="weekyears"><text/></attribute>
       </optional>
       <optional>
         <attribute name="weeks"><text/></attribute>
       </optional>
       <optional>
         <attribute name="weekdays"><text/></attribute>
       </optional>
       <optional>
         <attribute name="moon"><text/></attribute>
       </optional>
 
-      <!-- @COMPAT: The below attributes are invalid for date_spec -->
+      <!-- @COMPAT: The below attributes are invalid here -->
       <optional>
         <attribute name="yearsdays"><text/></attribute>
       </optional>
     </element>
   </define>
 
 </grammar>