He stinks! He loses numerous games because of time management, something you need experience with as a coordinator (getting plays in) or as a head coach. Herm is a nice guy. Gives a great press conference. But is a terrible gameday coach.
Watch NFL Network. The behind the scenes of the Ravens-Jets game. It was on a couple weeks back, they replay it often. The Jets sideline is a joke. They had no clue whats going on.
Then watch tapes of last years NE-NYJ game from Foxboro. And NYJ-Philly game from Philly last year. Herm isn't a head coach. No team will EVER promote a position coach to head coach ever again because of him.