The technical Oracle performance tuning section doesn't start until Chapter 5. The first 94 pages of the book is spent on topics such as "Maintain a Healthy Skepticism","Blame should be Avoided","The Cost of a Poor Working Relationship", and "The Universal Law of Reciprocity". Although the author's advice on these matters is sound, the first 94 pages clearly does not provide what the users are looking for.
The crown jewel of this book is its technical explaination of wait events. Its explaination of v$SQL, v$system_event, v$session_event, and V$Session_wait tables is well worth your money and your time. If you do not know of these tables, then do yourself and your Oracle users a great service and buy this book and master its contents. You will not regret it.
The weakspot of this book is in the resolution of Oracle's slow performance. Although the book provides strong hints that most Oracle issues can be resolved with better indexing and index hints, the book does not emphasize it as much as it should. It also doesn't provide a whole lot of suggestions on how to optimize the SGA.