I'm very good friends (my former home teacher) with the son of a former coach. They would have team members over for dinner on Sundays. He said McMahon was always the courteous and polite of the players (would help with dishes, and always played with the kids) but he ALWAYS had a chew in.

I love McMahon, and think he was the best QB in it's history, but he absolutely shattered the honor code and a blind eye was turned. LaVell probably maintained plausible deniability.