I agree with the premise of BPA, but there are so many other factors involved, especially in a specialized sport like football.
To me, having just won my first championship as a coach after being so close many times, it comes down to up front. We can have all the bells and whistles we want, but if we aren't strong up front, we're not a championship team.
In the NFL, you need to win in the trenches. I have often stated it starts with the QB, and I will not undermine the importance of that, but even Brady and Manning struggle when not protected.