Most here will agree that the "black belt" is but a starting point.
In my view it was a "high school diploma".
That got me to thinking about how we view/should view rankings.
IMO, they should be both physical ( ability to do) and academic ( ability to understand AND convey).
That said, we must also be aware of physical limitations and take those into accounts.
So, I have postulated thus:
4-5 years for a Black belt- "same time to get your high school diploma
4- years to get your "bachelors degree" - 2-3rd degree BB
4 years after Bach.Deg to get your masters.
2 years after that for your doctorate.
When are you a GM?
When those you have taught reach the degree of "Master".

So, for someone to be viewed as a "master" in a MA, they would have had to spend a minimum of 12 years doing that MA and be able to not only do it but also convey what it is as well as any other person that has a "master's degree" in any other subject.

Thoughts?