Not sure there have been any all-star/HoF players who have become successful coaches in the NHL, so far., aside from Martin St Louis, and we haven't had a large enough sample size with him, yet, to label him a succsessful coach. Even Craig Berube was a 4th line goon for most of his career. They've all been mostly NHL flunkies or bottom 6/bottom 3 players.
It's almost like being ridiculously physically talented at something has no bearing on the leadership, management, teaching, and strategic elements of sports. It's a rare treat when the two overlap.
And sometimes it's a detriment. I'm pretty sure Gretzky watched his players puck anticipation and shook his head wondering why they didn't see the play developing 3 steps ahead like he did. "Just know where to be before it happens, morons! Gah." Like how can you possibly teach what he did? You really can't.
Growing up there were kids at goalie camp that wanted to be Hasek. And yeah, Hasek was the best so it makes sense. But trying to emulate him was a disaster. He was one of a kind. You're better off trying to mimic boring but steady Osgood if you actually want to get better.
The truly elite players are rarely able to be replicated. But guys like Jeff Halpern? He worked his ass off for everything out there. If I'm teaching a youth hockey player, yeah it's fun up see Datsyuk highlights, but get real... he's going to learn more and find success following the fundamentals that made Halpern a professional.
Give me a roster of guys with the brain and drive of Halpern and you're going to go far in the playoffs.