Had never seen film of a Lombardi skull session before. (Was prompted to look up the "power sweep" by one of Buckeye Phi's posts). Now I understand why Lombardi was so revered by his players. Have never heard all aspects of a play so clearly thought out and described. I'd always thought he just yelled a lot.
https://www.youtube.com/watch?v=kmtVeqMt6dc