I bought this book from a store sale at 3$, and after reading this book, realized that it was not a bargain. This is one of the worst management books I have read so far. What the author did is take a few very simple and mostly useless ideas (do what is appropriate? Is this an idea?) and wrapped them in Musashi's 5 rings, giving them some Far East flavor and mysticism. If you are able to see through this and if you can summarize what the book is saying, it has a very simple message, and not a new one.
The message is not new, nor intuitively appealing. However, it is also a painful effort to get to the message, because the book is lacking organization and needs editing. Supposedly organized around 5 rings, each section contains several subheadings that have no obvious relationship to the section they belong. Especially in the first 2 parts several paragraphs lack focus, and contain sentences that are not supporting each other, nor binded to each other in a meaningful way.
Several examples are repeated all through the book, suggesting that the author might be having a tough time filling out 159 pages without repeating himself. I was disturbed when the same tiger example, or the same water example kept repeating all through the book, each time appearing as the first time and explained in detail.
The author fails to separate Musashi's writings from his own prescriptions, which was very disturbing to me. Some direct quotes contained sentences like: Musashi says "the competitive executive gathers together small pieces of information...." So should we believe that Musashi, who was a Samurai warrior, wrote up thinking about executives, or organizations?
Most of the prescriptions of the author are vague and cannot help anyone except if you are trying to make a post-hoc explanation for someone's success. I agree that timing is very important, but you cannot prescribe someone to exert appropriate amount of effort, or be at the right place at the right time. These are sufficiently vague prescriptions that no one can refute, but also mostly meaningless.
The author fails to specify the boundary conditions under which these prescriptions will hold. The author argues that business is a battle, and in order to win, you need to do these. However, not all business life is war, nor should be treated as such. If you are having an interpersonal conflict with someone you will have to continue to work after the conflict, try these techniques and guarantee that you will have no future together. Musashi was a samurai, and his teachings I think are related to conditions where you are having a battle to death. Under these situations, you need to do whatever it takes to win, including Musashi's ideas such as stabbing one in the eye. You cannot afford to apply these techniques in your work group, nor in most negotiation situations. I think in this respect the book is dangerous, because a novice who decides to take these ideas to heart may start to frame business life as war and win-lose situations, which is simply dangerous and wrong. If you treat the other party as enemy, he/she becomes your enemy, and this would be a self-fulfilling prophecy. I am not saying there are no wars in business, but I definitely argue that not all business life is war. The author should have clarified under which conditions these principles would apply.
Finally, I think the battlefield examples at the end are simply too convenient. The author tries to examine the success of Bill Gates, Andy Grove, Donald Trump among others with Musashi's teachings. I believe these successes can be examples in any organizational behavior or strategy textbook, and almost in any chapter. The real success of these tactics would be shown if these successful people consciously applied these so called tactics in their business life. As it is, they don't have much meaning.
With these points, this was a book that seriously outraged me from start to finish.