well, if you're anal and want to "do it right" because of some deep-seated masochistic tendencies, then sure.
if you're realistic and realize that the only place your code is going to see the light of day is in 4.x, then you might as well save yourself a few hours -- and the frustration when you miss a place, because you will -- and do it the easy way. :P
(And if someone did come along and say, "Hey, did anyone write a moderation patch for 3.2.5? I've heavily customized my own but I'd like to add this too," he will have a MUCH easier time patching in your code if you have compartmentalized it away from the "standard" like this rather than trying to MAKE it the standard for some future release that isn't going to happen any time soon.)
