I've seen Gata hanging around the Marshall CC. Also have a few other GM's who like to play there.
When they all play each other, they either gain or lose points. The go out an play other GM's who they dont play as much, and then their getting used to the changing style of play, and a different opponent.
If i played only a core group of players in a club for a long time, then played other players, it might be good or bad, depending on the mindset.
Just my thoughts.
Maybe kamsky got better, by playing a lot, and the other GM's got rusty.