pfren,
you missed the point. It is not about how the Super GMs are training now. It is about their journey and more importantly how they started out. I bet most of them played lots of blitz and bullet when they were untitled. Anyway, it is not even about that. The primary point is: is blitz useful for the beginners or not? Thats the point being addressed. I assume that untitled players are better suited to talk about what helps beginners to learn fast than titled players.
I can see what (almost) all those "experts" in this thread, which recommend to beginners playing a lot of blitz games, have in common:
They are untitled (but of course, they do know how superGM's are training- what the hell?).
Just a coincidence, I guess.