At page 19, I was not impressed. I was hopeful, however, that information in subsequent chapters will be accurate and useful and lacking in grammatical and spelling errors.
Chapter 3, on poses, I find it to be very helpful and well laid out. I like how the information in this section is laid out. I think the benefits section could be eliminated (or better researched), as it doesn't have rigorous scientific backing, and I'd like to see more in-depth discussion of what tissues each pose targets. Other than that, I have no critiques of this chapter, other than a couple typos/grammatical errors.
I do wish the poses came before a more in-depth discussion of flow and other things in chapter 2, as the naming of the poses is confusing, and should be included before any discussion of the theory or other aspects of the poses.
One gratifying and redeeming quality of this book is the quality of the photographs. The models are dressed in differing colors, giving the black-and-white photos less contrast. This helps the viewer to see more details in the positions of the bodies. There are some cases in which the models wear dark pants and use a dark bolster that make details difficult to decipher, but on the whole, the poses are easily viewable in the photographs.
Chapter 4, giving flows is wonderful. I love the many options it provides as well as the way the information is laid out in 3 levels. It's an excellent starting point for teaching yin yoga classes.
I was annoyed by Chapter 5. The main resource for chapter 4 is a forum on YinYoga.com. There are far more reputable sources to get information. There is a whole body of medical/scientific research on effects and dangers of yoga. I'm disappointed the author didn't access that information to inform this chapter.
Chapter 6 left much to be desired. There were a lot of terms thrown around without context or definition, which made the reading confusing. There were also more typos/spelling and grammatical errors. The elastic band metaphor was inappropriate, as it didn't relate to the main point of stretch in different temperatures.
Chapter 7 made a lot of claims that aren't backed up by science, and made a point that we, in the West over-rely on scientific proof. The problem with this perspective is ignoring the entire field of science, which is laughable at best. The other problem is that there is, in fact, a growing body of science to support many of the claims that yoga teachers make (not all of the speculative and curative claims, though), which is just entirely ignored. My other problem with this chapter is that, though I understand that the subtle body is, in fact, subtle, even experts in subtle body practices don't agree even for the location of the processes or even what some of the parts of the subtle body are.
Chapter 8 was very short, but it could have been shorter. I do think the discussion on gratitude was helpful and instructional. However, on the whole, the discussion on mindfulness was lacking in substance, although I appreciate the points on contraindications.
This book does have a lot of useful information, and isn't without merit, but it is very repetitive and lacks important information. My other critique of this book is that Mr. Clark seems to make up his own anatomy/medical terms, instead of using the terms that are already in use, which just makes his explanations confusing.