I think he was using clever use of game mechanics, but he looks like an idiot for basing his ability to get "world first" Inferno on being completely invulnerable to damage.
The fact that he made some stupid video about pulling out of an imaginary race made me laugh, though. This whole "world first" thing in Diablo is just some retarded ploy to get you to watch their streams or subscribe to their channels. They can't prove they're world first, only that they're the first ones in the world to post it. For all they know, some Korean gaming god is sitting there laughing at all of them as he progresses faster.