Make the wrap around GET parameters non-capturing
RewriteCond %{QUERY_STRING} (^|&)foo\=13($|&)
RewriteCond %{QUERY_STRING} (^|&)bar\=baz($|&)
is now generated as
RewriteCond %{QUERY_STRING} (?:^|&)foo\=13(?:$|&)
RewriteCond %{QUERY_STRING} (?:^|&)bar\=baz(?:$|&)
which makes the generated code easier to modify should you want to actually capture something, and is a very minor performance boost.