Even the first part not clearly explained like other books, the personas chapter is very good to present this good resource. It worth to keep in mind this phrase: “I think our users want this“, which is a common idea in developing / designing I’ve found between several people I know.
The second part keeps you engaged and the third part is very good since as the concepts are already explained the author can connect it through commonly used deliverables: Site Maps, Flow charts, Wireframes, Screen Designs.
The author try to advise some of the deliverables could be outdated in a short term due the fast developing in dynamic web sites, but I think rather to been outdated they will be adapted in newer models. The Software engineering field still using several techniques and ideas from the start of this field some decades ago and only have polish many of their techniques and models (of course also have developed new techniques and models like UML).
Without doubt a book to read and ground several concepts that are of daily use in usability working.