After listening to many yoga teachers anguish about the competition from other systems of yoga, I have come to the conclusion that if we dwell on the competition in the “yoga marketplace” we loose the essence of what yoga is about.  Yoga is about bringing ourselves into harmony and health.  It is not about a sweaty workout.  Often we sweat in an Iyengar yoga class, but only as a result of the hard work required to teach our bodies how to become more intelligent through attention to correct movement from muscles that have not move correctly.  Eventually, the work is about working smarter, not harder.  Working smarter is often as tiring as the hard physical work.  Working smarter forces the practitioner to take her/his attention inward.  We must be fully present as we practice without the distraction of music, incense, and other externalizing distractions.  Below is a link to an article that is what can happen when teachers get caught up in the commercialization of yoga.

The Colossal Failure of Modern Yoga