Just jumping in here... I agree that there's no Elo hell, but I don't agree with your reasoning.
There's alway gonna be edge-cases. Professional players are such edge-cases and therefore they aren't a deciding factor, when it comes to the existence of Elo hell.
Actually, the best argument against Elo hell, I've heard, comes from Riot's very own Phreak.
I can't find his post, but his point was, that if Elo hell is where you always lose, then someone else is winning all the time, which then means there's no Elo hell.