I record almost everything I teach and I suggest this practice to all Yoga Teachers at Lulu Bandha's or in our School.
This technique was first suggested to me by Erich Schiffmann. He said something like, "Write down what you are going to teach. Write down what you actually teach." I no longer plan my regular classes, but I blog out the results, and the class is recorded to video.
This discipline has created a mindfulness of how and what I am teaching. I can feel the sea changes before they come and see patterns emerging before I really understand them. When I am in a "transitional" spot and the flow of class is a little awkward, instead of feeling bummed, I feel excited cuz I know change is coming.
For example, I started teaching Yin Yoga again. I teach late at night, 7pm on Mondays and Wednesday. Just last night I became aware that part of me is trying to cultivate the feminine within me.
Over the last year, the subtle anatomy system has become an accepted part of all my classes. This was not a decision on my part, rather I watched it develop. Sometimes in class you can feel yourself carried along and be just as surprised at anyone else at what results. And if I don't record it, I forget.
This practice also bakes in the notes and patterns and various riffs that are developing, allowing me to understand more and absorb more. Simultaneously, the recording allows me to clear for the next time.