What is an “Advanced Yoga Practitioner”?

Recently, I took a yoga class after which the thought occurred to me that I had no business teaching whatsoever. It wasn’t because the poses were particularly fancy or that we were doing something I hadn’t done thousands of times before. It was just obvious that this particular teacher had an amazing base of knowledge. The wisdom she possessed was not necessarily a tangible thing, but it was powerful nonetheless. And it was something I felt I didn’t have.