There's a reason it's considered the standard text for endbands. Clearly written and well organized, it's not a book for someone without a little bookbinding background. If you've got a grasp of the basics though, working a headband from scratch is a great way to set your work apart or add a personal touch to a pre-made text block.
The strengths: Scope. All the major (and a few minor) styles are covered in depth and detail. Step by step instructions are clear and well illustrated. The drawings are reasonably clear most of the time (there are a few that could be improved).
The weaknesses: The inclusion of photos, even a black and white gallery at the end, would be a welcome addition. The brief description of the materials it the front could be expanded (I'm sure there's another whole volume that could be written on thread, but a little more detail about the types of silk thread and how to select it would be a great help).
Those are minor quibbles. The book delivers what the title promises, and the work is both fun and challenging (be prepared to cut off a few failures and start over a couple of times).