I think Doc is a great motivator, but he doesn't have the greatest substitution patterns nor does he handle PT consistently well.
He's a little bit Grady Little in the PT aspect, he kinda gives in to his players even when there may be better options available.
I agree Doc is a great motivator. If he has the best players, and they are all healthy, he can motivate them to win it all. That right there makes him a great coach.
But it doesn't male him the best coach in the league, as he does have the shortcomings you mentioned above. I thought he was Grady Little all along, myself.