This book came highly recommended to me by a work colleague, so highly in fact that I bought a copy for myself and a second copy as a gift item. Sadly, after having read the book, I can't understand what he saw in it. This book is disappointing because it promises the world, then delivers very little beyond platitudes and common sense.
Some books do a great job teaching common sense because they convey information we "already knew" in a way that makes us see things differently, or that sticks in our head so that we actually implement common sense, instead of saying "I knew" that and continuing old patterns of behaviour. "How to Win Friends and Influence People" is a great example of a book that teaches common sense in a way that will actually change how you act and how you think. By contrast, this book tells you things you already know in uninsightful and uninspiring ways.
An example of how the book fails to deliver is the chapter on cross selling. This is a very important issue for many professionals, and something is specific enough that an author should be able to give lots of practical, useful advice. Instead, the chapter is a only dozen pages long, and almost all of it is taken up with a discussion of how hard cross-selling is. I know this already, and even if I didn't, telling me it's hard doesn't help me do anything about it or improve my practice. The chapter closes with 1-2 paragraphs referring the reader to their general system of trust-building. That's not useful advice, it's specific, and it's not actionable. If you write a chapter on cross-selling, I expect you to tell me how to cross-sell. Not that I should have already figured it out from the rest of the book.
Speaking of their general system of trust-building... it's pretty silly and tough to take seriously. Yet they build the book around it. Specifically, the authors continually invoke an equation stating that trust equals: comfort plus skill plus rapport divided by self-centredness of the professional. I may be getting the exact qualities you add together wrong, but that really doesn't matter, because the whole idea is silly. It's common sense to say that people trust you based on a lot of things, and that some things increase trust and others decrease it. The false precision of a scientific formula doesn't help teach the principles of the book, nor is it a mnemonic tool that helps you remember their system. I really don't know why it was included at all, let alone made a core part of the book.