I appreciate the previous responses received, but I'll take this question in a slightly different direction. The following code does not do what I want. If I substitute back in the commented out line, I restore the functionality I want. Is there a way to format qr blocks such that they can be more easily read by the uninitiated? 
#!/usr/bin/perl

my $s = "blah,blah,blah <PgfTag `Normal \(T\)'> yadda,yadda,yadda";
print "s =\t\"$s\"\n";

#my $pattern = qr{\s*<PgfTag `Normal \(T\)'>\s*};
my $pattern = qr{
    \s*
        <PgfTag `Normal \(T\)'>
    \s*
};

my $k = 0;

$s =~ s/$pattern/++$k && ','/gex;

print "$k change(s)\n";
print "s =\t\"$s\"\n";

[download]
Thanks again for any comments passed on.

In reply to commenting regular expressions (take two)? by SeekerOKnowledge

Title:
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