It's a personal thing for sure, but in more than one way. Ben HATES their coach and I think you will see him have the game of his NFL career in this SB. One of the Ravens said "Ben is a sandlot player,
and a damn good one". There is no way to prepare for a QB that makes it up as he goes along. It's much easier to prep for a guy that's stands in the pocket like a mannequin. It's very tiring for a defense to be chasing around a QB the whole game. I think you saw that in the Ravens game. They were sucking wind in the 4th quarter and they didn't know where he was going to run to.
He doesn't know until he takes off.
You can only commit so many defensive people to one guy before you expose your secondary to big plays.
So it'll come down to a coach that has a personal grudge because he was passed by when they replaced Cowher, but who doesn't play on the field and can't do anything to personally affect the outcome of the game, and a QB that's playing great ball who has a 7-2 playoff record, a SB ring and more wins than any QB in NFL history with 5 years in the league that can. Who would you bet on?