Disclaimer: I'm an investment professional who's been using fundamental analysis to pick stocks since 2004. I was a skeptical when it came to technical analysis before reading this book, and I'll say right away that I keep being so after reading it as well.
"So why the heck did you pick it up?", you might ask. Let's say it was a personal exercise on open-mindedness. I've never actually stopped to do an in-depth reading on the subject and I think it was about time for me to do it. Robert Edwards' book seem to fit well for the job, as it's technical analysis targeted at long-term equity investing, which is as close to what I do everyday as the subject can be.
Guess what: despite the naive and non-sense criticism of fundamental analysis that the author lays out in the beginning of the book, I actually found some chapters enjoyable. It's a real marathon on technical analysis, very well written and full of examples to illustrate its principles. The chapter organization is very useful for later reference as well. I was still confused by some concepts, but I definitely got the gist of all of the core ideas. That doesn't mean I was not skeptical of most of them, though.
I still think that the identification of trends remain an extremely subjective discussion under a lot of circumstances, especially among folks who are not as experienced as the author. This might render the methodology less useful or very error-prone in a way that back tests are not able to catch. In other words, even after finishing the book you might have a lot of trouble to identify actual trends on current markets, given the unlimited possibilities and angles from which you can try to call them out.
In the end, I'm definitely not putting my personal or my clients' money under this approach, but in some ways I enjoyed the read. If you've already made your mind about using technical analysis to invest in the markets, then I would advise you to go for some of techniques in this book, as they might give you a way to start investing without imposing the potential damage to your assets that other technical methodologies that foster a lot more of short-term trading might do.