Theoretically, the content in this book is well organised, and it does contain some great information, advice, tips and excercises, as well as references to some very useful and important work. On that score, it is worth buying.
However, it is spectacularly badly designed. Some of the typefaces are so light they are barely legible; a lot of the structural and background graphics look home-made; the 'designer' (the author, one suspects) has no acquaintance with proper design-grids. This makes for what is sometimes a difficult and slightly maddening user-experience.
Had I seen the contents in advance, I might have thought twice about buying. That isn't to say that on second thoughts I wouldn't have made the purchase, but it did come as a disappointment to find that a book about such a fundamental field of design should have been so maladroit in its own execution.