One thing that hit me today - Don't know why I didn't realize this sooner:
Sean McDermott is a system guy.
Sounds like he has his mind made up that he has to run his defensive system. I know some other coaches who think that way. One of them just got fired from the Bills last season.
I guess McDermott is not the type of coach, nor probably has the experience to do so, who can take another team's defensive personnel and create the defense to best fit that personnel.
That is my first knock against the guy. But it is a significant one. Hope he gets the guys to fit his system. Not the type of coach I really wanted though. So far I like everything else about the guy that I have heard. But a guy stuck on his own system has me very concerned.