Earlier quoted context omitted.
It turns out he is a vimmer. I fully support his argument. BTW there is even a snippet/plugin that turns VIM into a typewriter by disabling any movement keys.
That explains why he said "You keep the fingers of your left hand on the ASDF keys and the fingers of your right hand on the HJKL keys." I haven't met any touch typists who didn't know the right hand is supposed to rest on the jkl; keys.
I'm a touch typist, and I keep my right hand on the AOEU keys and my left on the HTNS keys.
Cheers!