He knows his stuff where it comes to nutrition and protein synthesis. I am not a low bar squatter, but my back hurts just watching that. He is a bit, IMHO, overly sensitive when it comes to his form. He will fight you to the verbal death if you criticize his form. It is a shame.
I don't see how he is supposed to keep his back from leaning that way considering he has such long legs for his height.
I am 6'5" with very long legs too and I can't squat without leaning forward. It is not possible for me with a normal raw squat stance (ok maybe it is possible, but I haven't figured it out yet)
I will say that if he is going to lean that way, he should set his back that way the entire lift instead of letting it violently cave downward like that.