Just did the new Gary Kraftsow Therapeutic DVD, Upper Back, Neck, and Shoulders. It's excellent. A forty-minute gentle to moderate practice of viniyoga that promotes greater mobility in the neck and strength in the shoulder girdle.
Viniyoga is not a young person's style: it's slow and repetitive. The connection of the breath to spinal movement gives it a profundity that grows on you, however. When I was first teaching, I learned a ton about coordinating breath and movement from The Heart of Yoga. This book describes the basics of the viniyoga style, and it also contains a complete translation of the Yoga Sutras of Patanjali.(Desikachar's translation is not my favorite, but it's a great one to have on hand as a contrast to other translators, since it's remarkably spare and practical -- none of the bhakti slant that you see in the Iyengar and Satchitananda.)
It's always amazing to me that one teacher, Krishnamacharya, inspired such different styles. This dude was the heavyweight champion of yoga. This is him at 99.
He had three main disciples:
Patabhi Jois (pronounced like Joyce), who founded Astanga yoga, the vigorous, flowing style which led to the craze for power and vinyasa yoga in the health clubs of the US. Jois teaches out of Mysore, India. Astanga yogis can be found in vegan restaurants, Indie record shops, and tattoo parlors. They think people who practice other styles of yoga are pussies.
BKS Iyengar, who teaches in Pune, India. Iyengar Yoga is the kind where they hold poses a long time, use a lot of props, and are obssessive about alignment. Many prominent American teachers (Erich Schiffman, John Friend of Anusara fame, Rodney Yee) started out as devotees of Iyengar, but broke with him and started their own styles. Iyengar yogis can be found in yoga prop stores, graduate programs, and intensive psychotherapy. They think people who practice other styles of yoga are hacks.
And TKV Desikachar of Chennai, Krishnamacharya's own son, who taught Gary Kraftsow (though they are rumored to hate each other now) and the famous philosopher Krishnamurti. Viniyoga is by far the least commercially successful style of the three, and I don't know enough to make a generalization about its adherents. I did see Desikachar chanting the Vedas in a church on the upper west side a few years ago. His family was chanting with him, and it was a good vibe.
It's always amused me how every school of yoga claims to have the authentic goods. Maybe some day there will be a cage fight to settle it once and for all.