[nickcarraway]

As for Brady, he is judged solely and entirely on his performance on the field.

Not entirely. He's judge a lot on his teammates performance on the field.

[SmokingJoe]

To a certain extent. But then individual players, especially the quarterback, for the most part have to account for themselves. A great team can have bad players who are usually let go. Equally a bad team can have very good players, who are kept even as the bad players are let go.