I haven't read the book, but is the premise that asset price movements form a random walk? (They don't, and hearing it said that they do is probably my nerdiest pet peeve.)
The book really impresses upon the reader the difficulties of beating the market, and indeed talks a lot about random walks, but mostly it's about the efficient market hypothesis.
I should say that I also don't think this is the best description of how prices actually move, and over the years since I've read the book, I have come to no longer believe in the EMH. That being said, I do still think pointing people in this direction in general is the best thing I can do: even though these ideas will only take you so far, they remain academically productive, interesting, and useful... And most people would do better to approach the markets with more humility and less confidence. Those who are nerd enough to go beyond the EMH will undoubtedly do so on their own and at their own peril. :)
The book is very much in the tradition of Benjamin Graham's The Intelligent Investor, Warren Buffett's value investing style, etc.
