Well, the (very, very) occasional framerate drops tells me other wise. It has only dropped twice in my campaign (37 hours) but for that to happen on the PS3........
Well, it is. Shaky hands would kill your aim in this game, being that you don't get to re-aim after you shoot.
The only framerate drop was due to the grass... fix the grass and your fine.
Framerate drops happen a lot on the PS3, usually due to sloppy programming.
Aside from which... why couldn't aiming be handled the same way it is in the actual game.
just tie it to the analog stick if you needed.