Earl Weiss
Senior Master
Looking at this much more closely, it is actually a very deep consideration. I'd like to take a look at this from strictly a 'third part' position for a moment. Looking at TF's example of topping out at 2nd Dan if you never teach (even within the school), this actually isn't a bad idea at all. If you're not teaching, why would you need to go any higher ...
It is often said that success is a jorney, not a destination. I have viewed BB Ransks as mileposts along the journey. While one could learn all the techniques by XYZ rank, the ITF syllabus contains new material thru 7th. One could argue that you could stay a white belt and learn all that material as well.
I would say that as I progressed, the number of physical motions to be learned decreased, but there were often new insighte to those already learned.