You could change 
(?:
  |
  ( \( )
)

[download]
to 
(
  \(
)?

[download]
... unless you get queasy when you see quantifiers placed on capturing groups.
Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re^3: How do I avoid double substitution when replacing many patterns? by japhy
in thread How do I avoid double substitution when replacing many patterns? by kyle

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