Absolutely And, that was my point, though evidently not well made. Certainly, Brady and Bellichek profited from each other. However, it appears, at least after one season, that Brady was able to function much better without Bellicek than vice versa.
As far as Saban, there are many attributes required to being a good or great head coach. And, knowledge of the game is just one, and, I would argue, not even the most important. That he is such a great recruiter is part and parcel of his beign a great college head coach.