Coach, thanks for the drill. We teach our OL 4 basic fundamentals. Butt Down, Feet Apart, Hands Inside, Eyes to the Aiming Point. It works get for most of our blocks but like you point out here. The backside cutoff you have to RUN! At your clinic in 2016, you harped on always being in a position to fight pressure with pressure. Are you worried about this during the first few steps of the backside cutoff? Is it alright for lineman to crossover? We are teaching backside leg through the crotch of the defender.