Yoga for the Masses

I just read this article in the New York Times about how it's getting more difficult to find advanced level yoga classes. So many new people are trying yoga all the time, the demand for beginning classes has outpaced that for advanced classes at the moment. I've definitely noticed that as big yoga studios are turning out more and more teacher trainees, it's quite common to take a class taught by someone perfectly qualified but quite inexperienced. It's a bit harder to find a teacher's teacher, but I've had better luck at smaller yoga studios.