Not quite what I meant. I'm not reporting (hence the absence of a name) and it wasn't a snap to a player, just a general "turn 90 degrees quickly/precisely". He was good, but he definitely wasn't aimbotting.
I saw someone in an earlier game doing a 90 degree snap turn while playing (left and right) and I was wondering if that's considered cheating or not. If not, how does one do it?