Okay:
Snap roll is basically inducing a spin in level flight. It works better in WB than AH (I mean, in DOA I could snap roll with precision to fake a split-ess), but some planes do it better than others. The "stop moving your stick so rapidly" doesn't really work against stick stirring. It usually catches me when I'm in a buff and switching positions. But here's how stick-stirring works:
Contrary to popular opinion, it's all about small control movements. Your position and velocity is updated every half second, so if you do an ailer roll and rudder kick (yes, Andy, a kick) in one direction, then reverse within a half second, the FE will send a roll and yaw speed in one direction, and the pursuer will see you move in that first direction. Then you'll have reversed, and the opponent's FE will have to update a movement 2-4 times what you actually did. That's stick stirring.
Often it occurs by pilots who haven't studied much BFM, but who find tha this works. They have little idea what it looks like on the other side.