I think I found an explanation for OP's behavior, he said:

Quote Originally Posted by TheRealMadruck View Post
I know the Nier fights myself incredibly well! Yet I don't move away from aoes until I get some form of visual or audio indication of this fact. The cheater moved 5+ seconds away from the player targeted to the other side of the boss before any cast bar, boss movement, or boss turning, or any indicator happened what so ever. No amount of "farming" allows you to have powers of clairvoyance to move that early before a aoe event happens.
I think the OP pride himself so much on his skill and knowledge of the fight, that he can not fathom anyone can actually play better. So in order to protect his ego, the only acceptable conclusion is that anyone that seems to play better than him must be a cheater, 100%.