Oh, that clip, yeah that's a shitty one. Probably posted by someone wanting him to look legit, by mixing up legit clips with thrash clips.
But he can easily be cheating, but will get unbanned anyway, unless a 3rd party proves the cheat allegations, at which point Valve has no choice to make the ban stand.
VAC, and all other anti-cheats, should be out-sourced to an independent entity. Banning a top pro is like shooting themselves in the foot. It hurts a lot.