Why would he have to change his style of play? The whole philosophy of Sharks goaltending coaching has always been to let the guy stop the puck the way he does it and refine the mechanics of his style and Wayne Thomas has been great.
Whether you meant it or not, it sounds like you think reactionary goalies don't have a place in the NHL. Stalock is a very active goaltender in the crease. He's got happy feet and that's not a bad thing. And as far as I can see, he just needs to calm down during scrambles.
I don't think they have long shelf lives, that is for sure. And they are basically just the 1 hit wonder type of goalies. (That can produce sometimes 1 or 2 good years in the nhl and then they fall back down to earth hard).
The game i seen live with stalock (way to long ago to count as now), but if that game is any indication of what he is still like it is definately bad. But i kind of getting the feeling he has kind of calmed his reactionary motions down a little.
In the game i seen, he would litterally move to the other side of the net on a point shots that would just miss the net on the side of the net he just left open.