Being a distinguished player doesn't necessarily make anyone an outstanding coach. Plenty of great players are terrible coaches, and many great coaches were marginal players.
Yes, very true but people have been sending their kids to him for more than 20 years and many continue to return to his camps, events and projects so he must be doing something right. His technical skills and teaching are top notch but not for everyone. Most kids can get past the gruffness but if not, then there are other good coaches who are more personable.