I'm sorry, but to me, all you have to do is look at the difference in the players from the time they start their career at SU, till the time they are finished their career at SU, and see the improvement to tell how good the coaching has been.
Not all players will respond to coaching. So all coaches will have examples of players who never truly succeeded. And the great players would probably succeed, even if i coached them.
Where the greatness of a coach comes into question, is that middle ground of player, who needs coaching to really reach their capabilities.
Obviously, it is purely conjecture as to how close any coach can get that player to his peak. I would assume that for many kids, this very idea plays a part in his decision to go to a certain school.
Obviously, many kids thought that JB was the right person to get them to reach their capabilities.
I, myself, can think of many kids who have played for SU, over the years, who vastly exceeded my expections for their careers. On this past team, alone, I think we can almost all agree that there was never any expectation that Scoop could improve as much as he has in his time on the hill.
In this case, a dare someone to argue that JB was not a great coach for Scoop.