Well, I think that you can always get stronger at a set body weight. Neural adaptation, better muscle fiber recruitment, etc... but at some point I think that in order to accelerate gains you would not be unwise to put on some weight... assuming it suits you to do so. I'm with you, Hrdgain, I am 200lbs and I wouldn't want to be even .5lbs over. Why? Because I compete in a weight class and it is important to me that I stay at the top end of the 175-200lb class and not at the bottom side of the 200-230 class. I have an advantage now, but it could easily become a disadvantage should I gain a lb.

All that being said, I would be willing to bet that I would be stronger (move more weight) at 230 than I am now, though that isn't to say I can't get stronger at my current weight, it is just more difficult. Maybe that is in part to not really getting to eat above maintenance too. Well, that and the fact that I've been in the gym for a darn long time. So all those beginner's gains are long gone and I have to fight pretty hard to get ahead now.