I'm a trainee yoga teacher and this is quite possibly my favourite asana/posture book in my fairly large library of yoga texts. Things I like which justify my 5 star rating and recommendation of the book to other readers are:
1. It is not aligned to any particular school of yoga. The majority of postures you'd find in Ashtanga, Sivananda, Iyengar, Bikram and Bihar schools are listed.
2. Unusually this book also gives build-up poses and counter-poses for each posture. It also identifies what the effect (energising, calming, strengthening etc.) for each pose is. You won't find these things in many other books and it's useful if you practise on your own to be aware of this and want to construct your own lesson plans.
3. Multiple modifications to make any posture easier or harder are also identified. I think these are clearly explained and practical.
4. The author is strong on alignment and also the subtler aspects of yoga. The language makes it clear that it's not about getting the perfect pose, but about experiencing the sensation of the posture in your body.
I concede the point raised by one reviewer that the photographs demonstrating the postures are of the full expression and not for the beginner or intermediate positions. Because of this I'd agree that the book will be most valuable to those who are fairly experienced. That said, I think it can be helpful to see the full posture and start working towards it as a long term goal measured in years rather than months. It would have been useful if the author had further categorised each posture into Beginner/Intermediate/Advanced. To somebody experienced it's pretty obvious which is which but to beginners it may not be clear (the conundrum "is it just me who think that looks hard or would any normal person feel this way?").
I agree with other reviewers that the binding is a nuisance but this is unfortunately the norm rather than the exception for yoga books (Swenson's Ashtanga book is an exception).