Technical books are usually not rated on entertainment value, and this book is no exception to that rule. Going through examples can be valuable, but can take a while.
Fortunately for the authors, this book has a lot of utility. There aren't a lot of books on design patterns for HTML & CSS, and this book has left me wondering why. (There should be.)
The authors have put together a book with 20 chapters full of design patterns that help you understand HTML & CSS, and how they work together to create the fundamentals of layout on the web.
I recommend the book, and if you buy it, do yourself two favors: buy a current edition (things have changed), and rewrite every design pattern's code for yourself and reproduce the screenshot given in the book. (For bonus points, use git along the way, and sharpen your day-to-day techniques.) You'll walk away with a much better understanding of both HTML & CSS.
While Pro HTML & CSS Design Patterns lacks a top down model to help you truly grok HTML and CSS, that's a common problem with all instruction in this area. (Another book opportunity.)
This isn't about entertainment. Do the work, and this book will pay you back.