I've always had the most problem with ... the ball in the air, helmet-to-helmet stuff. When the ball's in the air, a defensive back is told to go get the ball. There's posters all over the playbook - see what you hit. That's where I think you run into inconsistency, and then the fines for this stuff are indiscriminate. It's like a kangaroo court.
— Bill Parcells
AirBallHelmet