Eric.
You are correct that lower level players probably will see greater benefits, simply because they have so much more room for improvement. My point was simply that even at the top level, those players understand that any little edge they can get could be the difference between winning and losing.
As both Chris and Scott pointed out, there are several pros who know that a few minutes spent honing their fundamentals is part of maintaining your top level.
Them players at the top of our game are there because they pay attention to every detail of their game. MDs are just a part of it.
Thank you for your kind words of support for instructors.
Steve