ROFL!! He'll have to add a whole new player's worth of moves to compensate. He'll still be good and effective, especially in that offense and playing with Nash, but he will rely have to expand his game.
You're right, if he can't explode anymore, Stoudemire can still be a good player, he's big and strong, etc. He'll have to remake his game as Shawn Kemp tried to do, and how Webber has done. Only Kemp did not have to do it so early, and Webber always had the skills.
I am really rooting for Stoudamire to come back big. Even if he expands his game tremendously, if he loses his athleticism there will always be a "what if?" when he is talked about.
oohah