I'm not yet a black belt so you may or may not value my opinion on this but I have worked as a teacher in the past and so I know from experience that you really start to learn your subject once you start to teach it to others.
I have just been reading David Lowry's book - Moving Toward Stillness - and there is a chapter called 'Climbing the circular ladder'. In this chapter he recounts an occasion when he was a junior ranked judoka and was witnessing some fellow students receiving their black belts at a tournament that they had earned by virtue of demonstrating skill in competition (batsugun). The belts were awarded by the panel of tournament judges who each imparted words of encouragment to the five recipients of the black belts. The most revered judge was Nishimoto sensei, a Buddhist priest and 5th dan in judo. They all waited for his words of wisdom. He stood up and, addressing the new black belt students, said,"You have taken a bit step forward. Now I hope you will take a big step back." Then he sat down.
The point David Lowry was trying to make with this anecdote was that learning in martial arts is circular, not linear, and we all have to keep taking a step back and revisiting basic skills again, each time gaining new insights and improving our own proficiency.
Becoming a shodan is an ideal time to step back and revisit some skills learned long ago in earlier grades and the best way to do that is to teach them to someone else. I think this is an ideal way to consolidate on learning that has already taken place over the previous few years, check your own understanding of it and complete another loop in the spiral of learning. As long as students still receive instruction from the senior instructor and assistant instructors are properly supervised then everyone can benefit.
Ref: David Lowry - Moving towards stillness (2000). Tuttle publishing
Other posts on this subject:
Do Black Belts have to teach (Just a thought)
Black belts and teaching (State of My Arts)
Do Black Belts have to start their own class? (Martial Arts and Modern Life)A Delicate Balance (Bushido Road)
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