Aight, here's the thing. This book is boring. yup. boring. And you're thinking, "Well, if it's boring, then why'd you give it 5 stars?". Because as a musician you have some choices to make. Playing exciting material poorely, or... play boring material well so that you can play exciting material well.
When I purchased this book I had recently made the decision to switch to a fluid 4 finger right hand method. And this book, although written for left hand method, has the potential to help you mentally seperate all 8 of your primary usable digits. I wrote out opposable right hand patterns to play the written left hand exercises, and I must tell you it has been a journey. But then again I think I've probly doubled in ability in the last year and I attribute much of that to this text. If you purchase this book and practice one of these a day, starting at 60bpm and working to 180, while using at least 12 positions for 20 or so minutes... I guarentee you, you will be a stronger bassists. But then again thats a lot of commitment. If your looking for simple chop builders this might not be for you. Although these exersices are relativly simple, they still require a strength of will.