He can make us all shut up and eat our words by simply taking a video of him moving and using skills in prime time (5 red dots) CH.1 Fedimian near the auction NPC. I think his “always above or at 25 FPS” is BS, but I’d be happy to be proven wrong.
Of course, Fedimian’s FPS drop is only barely comparable to the skill spam world boss and GvG entails. But his claims were solely for CH.1 Fedimian, so he only has to prove that much.