Aim assist is just that: an assist. Other than helping you lock onto your target a little easier, it does very little to ensure the player gets a kill. It doesn't help improve a players reaction, aims their weapon for them, balances recoil, or anything like that. The only way you notice aim assist is because your gun is flying all over the place (even with recoil) when you're shooting at someone.
Could players do well without aim assist? Sure, but why would they take it off when it can give them an edge over an opponent and secure that kill? As long as it's in the game and its not cheating by any means, why wouldn't you use anything to your advantage? Also, turning of aim-assist proves nothing...except maybe to yourself. It is a good personal challenge to try and do, I'll give you that...especially with sniping.
BO2 can be laggy at times and everyone has been killed by weird circumstances before. When lag is involved, sometimes character animation moves faster than their actual hit boxes and that's how you get kills/killed even though it looks like the bullets missed. The hardscope/quickscope thing has been beaten to death...
Hi Phil, I respect that and it's a fully valid answer :-)
I guess it's more from a philosophical standpoint to me.
Why not use something that would give you an advantage? Pure and simple, pride and honour, to be able to say no assists, that kill, that score, was all me. The same way you typically don't see adults bowling in an alley with bumpers on the sides.
Aim-assist seems a way of catering to the lowest common denominator. Another means of diluting the gaming gene-pool and I am by no means a purist, whatever people play is entirely up to them but a certain standard should be held, especially in a game that gets played at a competitive level. Why water it down when you can breed a better gamer, better competition?
My introduction to multi-player was Quake II and those days, with no lag compensation, aiming ahead of your target... There were two options, play a against brick-wall learning curve and get better or go home. It was frustrating but it was more rewarding to play because you had to earn it. Important point here, I am in no way implying any game should be as brutal as Quake to learn, that borders on masochism lol