I learned yoga from TKV Desikachar, S Ramaswami, and Gary Kraftsow. They taught me that yoga is the art of concentration. I also learned that I had to understand fundamental mechanics of movement to know whether my practice was useful or not. Good alignment is not universal, it's individual. The students who come to me want to receive the transmitted knowledge of breathing as a concentration exercise, and movement analysis to know whether their efforts are fruitful or not.