A key tenet ("presupposition") of NLP is that *nothing* works for *everybody*, and *nothing* works for *anybody* *all* of the time. You have to try things out until you find the exercises and methods that work "for you". And even then you may find that they work better some days than others.
After reading quite a few books on NLP, I'd say that this is the nearest thing you'll find to the essence of NLP short of going on a "top notch" training course. Read the book, and DO do the exercises, but only when you're ready to progress your life to a whole new level.
For those who are ready for something better - highly recommended.
If, on the other hand, you're really not sure if you're ready to step out of your "comfort zone", then stay clear of this book. Once you've read it, you'll never be able to put things back the way they were.