@ demi: I don't particularly disagree. I'm the most obvious optimizer in my group. When I call optimization 'not inherently unproblematic', I mean pretty much what you describe, but I do believe the optimizer is just as much to blame for any problem developing as the non-optimizers. And I think in a forum where optimization often seems the obvious thing to do, it bears mentioning (and rementioning) that you need to do so with some thought.
My optimizing is very rarely a problem in my groups, and the OP seems to be having problems. Hence this whole sticking up for the side I'm actually not on.