Kaufman's whole treatise on RISK is really worth the price of the book. Understanding risk and it's effect on your psychology is an important and very valuable treatise. Kaufman does a very good job on the subject. Also of benefit, is the Adaptive Moving Average algorithm. While this is also part of Metastockhaving the formula is invaluable for those of us who want to modify it.
The weakest part is the computerized system analysis at the end is old and rather simplistic; I would not recommend it. Some of the ideas are interesting but Pardo's book is much much better.
Now, aside from the trading methodology which is well written, there is a lot and I mean a lot of Programming Language in the text. I don't want to take away from the concepts which were great, but if you are not planning on writing a computerized trading program you may want to search elsewhere. On the other hand, if you are working on a "Black Box" trading system, I would highly recommend this text.