This book lacks any intellectual rigor or statistical proof that it works, it provides a set of taxonomies that are helpful for classifying areas, but gives you no clear way to evaluate. If this work had not existed in one form or another since the 60s, that might be excusable, but there has been adequate time to test this; instead, the authors have made much money marketing this book that emphasizes a magical thinking approach to testing. This is exemplified on page 25, when one of the authors recounts how he delivered a full version of his training to upper management. He states that he had no idea if it had any effect on increasing management support or effectiveness, but he is confident that it was helpful. This is something that could be easily tested, and he aptly chooses to ignore it based on personal confidence. While confidence can sell books and give the false impression of competence, it lies in the area of magical thinking where good employees can lose their jobs. Scholarly articles on the subject concur. The taxonomies are a helpful starting point, but there needs to be, as Shakespeare wrote, "More matter, less art."