Perhaps both the strength and the limitation of this book is that passion for the subject is avoided. This doubtless helps avoid mistaking ideas about breathing for actual breathing. On the other hand, someone stumbling upon this book may under-appreciate the benefits of better breathing. Some may consider the discussion of smaller muscles and the smaller movements unimportant and diluting the interesting parts. However, if one wants to really change breathing then it is beneficial to know every part because in effective breathing, everything works in harmony. Changing my breathing has helped change my life, and it was this book, not my first book on the subject, which gave me clues on how to change my tendency to paradoxical breathing. (I had to find a way to stop my lower ribs from pulling up and flaring out in disproportion when my diaphragm pulled on them, so that the center of my diaphragm could instead pull itself down.) Together with a book that covers the motivations and goals of better breathing, say by Dennis Lewis, this book is well worth it the cost and the study.