diff --git a/cts/cts.in b/cts/cts.in
index 695400c550..7be16576b1 100755
--- a/cts/cts.in
+++ b/cts/cts.in
@@ -1,264 +1,313 @@
 #!@BASH_PATH@
 #
 # Copyright 2012-2023 the Pacemaker project contributors
 #
 # The version control history for this file may have further details.
 #
 # This source code is licensed under the GNU General Public License version 2
 # or later (GPLv2+) WITHOUT ANY WARRANTY.
 #
 
 # e.g. /etc/sysconfig or /etc/default
 CONFIG_DIR=@CONFIGDIR@
 
 cts_root=`dirname $0`
 
 logfile=0
 summary=0
 verbose=0
 watch=0
 saved=0
 tests=""
 
 install=0
 clean=0
 kill=0
 run=0
 boot=0
 target=rhel-7
 cmd=""
 trace=""
 
 custom_log=""
 patterns="-e CTS:"
 
 function sed_in_place_remotely() {
     cluster-helper -g $cluster_name -- cp -p "\"$1\"" "\"$1.sed\"" \&\& sed -e "\"$2\"" "\"$1\"" \> "\"$1.sed\"" \&\& mv "\"$1.sed\"" "\"$1\""
 }
 
 
 helpmsg=$(cat <<EOF
 Usage: %s [options] {[CMDS]}
 
 [--]help, -h            show help screen and exit
 -x                      turn on debugging
 -a                      show relevant screen sessions and exit
 -c,-g CLUSTER_NAME      set the cluster name
 -S                      show summary from the last CTS run
 -s                      show summary for the current log (see -l)
 -v                      increase verbosity
 -p                      (currently unused)
 -e PATTERN              grep pattern to apply when 'summary' or 'watch' requested
 -l                      print the filename of the log that would be operated on
 -w                      continous (filtered) monitoring of the log file
 -f,-sf FILE             show summary for the provided log
 -t TEST, [0-9]*         add a test to the working set
 [--]kill                request termination of cluster software
 [--]run                 request CTS run (passing remaining arguments through)
 [--]boot, start         request CTS run (with --boot option)
 [--]clean               request cleaning up after CTS run
 [--]install, --inst     request installing packages to get ready to run CTS
 trace-ls, tls           list traced functions
 trace-add, tadd FUNC    add a function to the list of traced ones
 trace-rm, trm FUNC      remove a function from the list of traced ones
 trace-set, tset FUNC    set function(s) as the only to be traced
 (f|fedora|r|rhel).*     specify target distro
 --                      delimits tests that follow
 EOF
 )
 
 while true; do
     case $1 in
 	-h|--help|help) printf "${helpmsg}\n" "$0"; exit;;
 	-x) set -x; shift;;
 	-a)
 	screen -ls | grep cts
 	exit 0;;
 	-c|-g) cluster_name=$2; shift; shift;;
 	-S) summary=1; saved=1; shift;;
 	-s) summary=1; shift;;
 	-v) verbose=`expr $verbose + 1`; shift;;
 	-p) shift;;
 	-e) patterns="$patterns -e `echo $2 | sed 's/ /\\\W/g'`"; shift; shift;;
 	-l) logfile=1; shift;;
 	-w) watch=1; shift;;
 	-f|-sf) summary=1; custom_log=$2; shift; shift;;
 	-t) tests="$tests $2"; shift; shift;;
 	[0-9]*) tests="$tests $1"; shift;;
 	--kill|kill) kill=1; shift; break;;
 	--run|run) run=1; shift; break;;
 	--boot|boot|start) boot=1; clean=1; shift; break;;
 	--clean|clean) clean=1; shift;;
 	--inst|--install|install) install=1; clean=1; shift;;
 	trace-ls|tls) cmd=$1; shift;;
 	trace-add|tadd|trace-rm|trm|trace-set|tset)
             cmd=$1; trace=$2; shift; shift
             if [ -z "$trace" ]; then
                 printf "${helpmsg}\n" "$0"
                 exit
             fi;;
 	f*)
 		target="fedora-`echo $1 | sed -e s/fedora// -e s/-// -e s/f//`"
 		shift;;
 	r|rhel) target="rhel-7"; shift;;
 	r*)
 		target="rhel-`echo $1 | sed -e s/rhel// -e s/-// -e s/r//`"
 		shift;;
 	--) shift; tests="$tests $*"; break;;
 	"") break;;
 	*) echo "Unknown argument: $1"; exit 1;;
     esac
 done
 
 # Add the location of this script
 export PATH="$PATH:$cts_root"
 which cluster-helper &>/dev/null
 if [ $? != 0 ]; then
     echo $0 needs the cluster-helper script to be in your path
     exit 1
 fi
 
 which cluster-clean &>/dev/null
 if [ $? != 0 ]; then
     echo $0 needs the cluster-clean script to be in your path
     exit 1
 fi
 
 if [ "x$cluster_name" = x ] || [ "x$cluster_name" = xpick ]; then
     clusters=`ls -1 ~/.dsh/group/[a-z]+[0-9] | sed s/.*group.// | tr '\n' ' ' `
 
     echo "custom) interactively define a cluster"
     for i in $clusters; do
 	echo "$i) `cluster-helper --list short -g $i`"
     done
 
     read -p "Choose a cluster [custom]: " cluster_name
     echo
 fi
 
 if [ -z $cluster_name ]; then
     cluster_name=custom
 fi
 
 
 case $cluster_name in
   custom)
     read -p "Cluster name: " cluster_name
     read -p "Cluster hosts: " cluster_hosts
     read -p "Cluster log file: " cluster_log
     cluster-helper add -g "$cluster_name" -w "$cluster_hosts"
     ;;
   *)
     cluster_hosts=`cluster-helper --list short -g $cluster_name`
     cluster_log=~/cluster-$cluster_name.log;
     ;;
 esac
 
+# NOTES ABOUT THESE AWESOME REGULAR EXPRESSIONS:
+#
+# * We can't assume GNU sed.  Unfortunately, + and * are GNU extensions.  Thus,
+#   we have to use {1,} for + and {0,} for *.
+# * You don't need to add an extra set of escaped quotes around the sed expression
+#   arguments here - sed_in_place_remotely will do that for you.
+# * Only literal quotes need the triple backslashes.  All other special characters
+#   are fine with just a single one.
+# * sed needs a LOT of characters escaped - \, {, }, (, ), and | at least.
+
 if [ x$cmd != x ]; then
     config="${CONFIG_DIR}/pacemaker"
     case $cmd in
 	trace-ls|tls)
-	    cluster-helper -g $cluster_name -- grep PCMK_trace_functions $config
+	    cluster-helper -g $cluster_name -- grep "^[[:space:]]*PCMK_trace_functions" $config
 	    ;;
 	trace-add|tadd)
 	    echo "Adding $trace to PCMK_trace_functions"
-        sed_in_place_remotely "$config" "s/.*PCMK_trace_functions=/PCMK_trace_functions=$trace,/"
+        # Note that this only works if there's already a PCMK_trace_functions line.
+        # If there isn't one, create it with trace-set first.
+        #
+        # Match optional whitespace; then PCMK_trace_functions; then an equals
+        # surrounded by optional whitespace; then an optional quote; then whatever
+        # else (presumably, this is the list of previously traced functions with
+        # an optional trailing quote).  Replace the entire line with
+        # PCMK_trace_functions=<new_fn>,<previous trailing line contents>
+        sed_in_place_remotely "$config" "s/^[ \t]\{0,\}PCMK_trace_functions[ \t]\{0,\}=[ \t]\{0,\}\(\\\"\{0,1\}\)\(.\{1,\}\)/PCMK_trace_functions=\1$trace,\2/"
 	    ;;
 	trace-rm|trm)
 	    echo "Removing $trace from PCMK_trace_functions"
-        sed_in_place_remotely "$config" "s/.*PCMK_trace_functions=\\\\\\(.*\\\\\\)$trace,\\\\\\(.*\\\\\\)/PCMK_trace_functions=\\\\\\1\\\\\\2/"
-	    ;;
-	trace-set|tset)
-	    echo "Setting PCMK_trace_functions to '$trace'"
-        sed_in_place_remotely "$config" "s/.*PCMK_trace_functions.*/PCMK_trace_functions=$trace/"
-	    ;;
+        # A bunch of simple regexes are easier to follow than one giant one.
+        # Look for $trace in the following places on any line containing
+        # PCMK_trace_functions near the beginning:
+        #
+        # (1) At the start of a list -
+        #     Match one of a leading quote, or an equals followed by optional
+        #     whitespace; then $trace; then a comma.  Replace $trace with whatever
+        #     came before it.
+        # (2) In the middle of a list -
+        #     Match a comma; then $trace; then a comma.  Replace $trace with a
+        #     single comma.
+        # (3) At the end of a list -
+        #     Match a comma; then $trace; then one of a quote, whitespace, or
+        #     the EOL.  Replace $trace with whatever came after it.
+        # (4) All by itself -
+        #     Match one of a leading quote, whitespace, or equals followed by
+        #     optional whitespace; then $trace; then one of a trailing quote,
+        #     whitespace, or the EOL.  Replace $trace with whatever came before
+        #     and after it.
+        sed_in_place_remotely "$config" "/^[ \t]\{0,\}PCMK_trace_functions/ { \
+                                            s/\(\\\"\|=\|[ \t]\{1,\}\)$trace,/\1/ ; \
+                                            s/,$trace,/,/ ; \
+                                            s/,$trace\(\\\"\|[ \t]\{1,\}\|$\)/\1/ ; \
+                                            s/\(\\\"\|[ \t]\{1,\}\|=[ \t]\{0,\}\)$trace\(\\\"\|[ \t]\{1,\}\|$\)/\1\2/ }"
+        ;;
+    trace-set|tset)
+        echo "Setting PCMK_trace_functions to '$trace'"
+        # Do this in two separate sed commands:
+        #
+        # (1) Unconditionally remove any existing PCMK_trace_functions= lines.
+        # (2) Add a new line with $trace after the example line, which therefore
+        #     must exist.  Note that GNU sed would support "a PCMK_trace_functions=$trace",
+        #     but that's an extension.  For all other seds, we have to put the
+        #     command and the text on separate lines.
+        sed_in_place_remotely "$config" "/^[ \t]*PCMK_trace_functions/ d ; /^# Example: PCMK_trace_functions/ a\\\
+PCMK_trace_functions=\\\"$trace\\\""
+        ;;
     esac
     exit 0
 fi
 
 if [ $run = 1 ]; then
     install=1
     clean=1
 fi
 
 if [ $clean = 1 ]; then
     rm -f $cluster_log; cluster-clean -g $cluster_name --kill
 elif [ $kill = 1 ]; then
     cluster-clean -g $cluster_name --kill-only
     exit 0
 fi
 
 if [ $install = 1 ]; then
     cluster-helper -g $cluster_name -- yum install -y pacemaker pacemaker-debuginfo pacemaker-cts libqb libqb-debuginfo
 fi
 
 if [ $boot = 1 ]; then
     $cts_root/cts-lab -r -c -g $cluster_name --boot
     rc=$?
     if [ $rc = 0 ]; then
 	echo "The cluster is ready..."
     fi
     exit $rc
 
 elif [ $run = 1 ]; then
     $cts_root/cts-lab -r -c -g $cluster_name 500 "$@"
     exit $?
 
 elif [ $clean = 1 ]; then
     exit 0
 fi
 
 screen -ls | grep cts-$cluster_name &>/dev/null
 active=$?
 
 if [ ! -z $custom_log ]; then
     cluster_log=$custom_log
 fi
 
 if [ "x$tests" != x ] && [ "x$tests" != "x " ]; then
     for t in $tests; do
 	echo "crm_report --cts-log $cluster_log -d -T $t"
 	crm_report --cts-log $cluster_log -d -T $t
     done
 
 elif [ $logfile = 1 ]; then
     echo $cluster_log
 
 elif [ $summary = 1 ]; then
     files=$cluster_log
     if [ $saved = 1 ]; then
 	files=`ls -1tr ~/CTS-*/cluster-log.txt`
     fi
     for f in $files; do
 	echo $f
 	case $verbose in
 	    0) cat -n $f | grep $patterns | grep -v "CTS: debug:"
     		;;
 	    1) cat -n $f | grep $patterns | grep -v "CTS:.* cmd:"
     		;;
 	    *) cat -n $f | grep $patterns
 		;;
 	esac
 	echo ""
     done
 
 elif [ $watch = 1 ]; then
     case $verbose in
 	0) tail -F $cluster_log | grep $patterns | grep -v "CTS: debug:"
     		;;
 	1) tail -F $cluster_log | grep $patterns | grep -v "CTS:.* cmd:"
     		;;
 	*) tail -F $cluster_log | grep $patterns
 		;;
     esac
 
 elif [ $active = 0 ]; then
     screen -x cts-$cluster_name
 
 else
     touch $cluster_log
 
 #    . ~/.bashrc
     export cluster_name cluster_hosts cluster_log
     screen -S cts-$cluster_name bash
 fi