I really like how the book is written. It gives a good overview on the different approaches and gear. Yet the author finds a way to give his recommendations and explain why he thinks it's the best route for him.
Instead of seeing only excellent images in this book, we also see the path to those images as the author explains how he works. Seeing the "not-there-yet" images is far more valuable than just the "Look at how pretty pictures I can take". The approach to good photos is understandable and clearly explained. It seems that in a variable environment even the pro's take multiple images to get what they want. They'll just have more experience to understand what to change and how much.
I've found many little things that I did just not understand about my speedlite and I'm now really inspired to explore further in photography. Many times I felt "there has to be a better way to do this", now I know.
The only thing in the book that bugs me a little bit are the feet, inches and other weird measurement units that are uncommon to me as I use metric in my everyday life. Sure, I can convert those in my head somewhat easily, but it breaks the flow of reading. Still, this is only a minor problem and short of making two versions of the book I could not think of any good solution for this problem. (having all those figures in both units would be a mess too)