This book is pretty odd. It is written by two gentlemen who appear to be the founders of the World RPS (rock, paper, scissors) society, which has in the past run tournaments around the world for RPS. This book really does explain some of the strategy involved with the game, and the last chapter includes some nice basic explanation on how to setup a tournament.
However, there is also a lot of obvious lies and balderdash in this book. The entire first chapter is completely made up hokum about the "history" of the game, which is an obvious parody of other historical sports literature. The problem is that it can be hard to tell the truth from the balderdash. There is some stuff in here that I know is true from experience, (i.e., the Japanese variant of the game called 'Attche, Muite Hoy!') but it will be back to back with ridiculous stuff like how RPS is used for highly dangerous illegal street gambling, and how serious professionals should always avoid such games.
So, this book is kind of entertaining, and if you enjoy playing RPS the strategic discussions have some value, but there is a lot of ridiculous stuff in the book that you have to deal with, as well.