Instruct: Classify Amazon reviews into positive or negative sentiment
Query: A Wonderful Guide to Ashtanga Practice

David Swenson is a fantastic teacher. In this book and in the related video, he comes across as a caring, careful guide to breathing and asanas. He emphasizes practice, but also lets you know why you are doing what you are doing. And he does so in a way that is neither patronizing nor pseudo-mystical.As I am not particularly limber, I liked his allowances for those of us who are not able to reach the full extent of the pose. Other teachers can be somewhat exclusionary, and even virtuosic in their practice, and David - despite being amazingly flexible - is not.The fact that the book is spiral, and thus ideal for use when you are on the mat, is indicative of the thought David puts into his books, videos, and, I imagine, his courses.I have been using this book for two years, and I imagine I will be doing so for a long time to come.