Exactly why do you consider Pepper a proven commodity? For 13 years in NE, he bounced around as a defensive assistant, never really given any meaningful promotion. Suddenly, he was kicked to the curb for reasons unknown. Next, he "coaches" one of the best D-lines in the NFL under a great DC. Next, another great defensive mind becomes Bills HC and he's again an afterthought. I would say the only thing he's proven is that he's a big question mark. I wish him all the best though.