Well, your first line is the identity transformation, which isn't removing anything. ;-)
The parentheses surrounding the ?# are part of the syntax; that is, the comment marker in a regexp begins (?#, not ?#. (Check perlre: all the "funny" extended-pattern elements start with (?, one of the reasons being that it's a mnemonic to "question" what's coming next.1) Thus if you're removing the comment you should remove the parentheses as well.
1I don't buy the explanation, by the way, but it's there..
In reply to Re (3): Yet another regex bug.
by VSarkiss
in thread Yet another regex bug.
by japhy
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