For the sake of the brevity that this book promotes I will say that " this book is Josh Kaughman's TED Talk except far less charming plus seven hours of material that adds nothing to the message"
The first part of the book where Kaufman talks about the principles of skill acquisition is the core of this book. After that, the chapters on his personal skill acquisition provides good examples of how it can be done, but it is not necessary to listen to them all. Kaufmann does an excellent job in narrating his own book with clear diction and a calm voice which makes it easily possible to listen to this book in double speed.
The theme of this book can be summed up by the title. If you want to learn anything, spend 20 hours doing it. While it does not contain a lot of new information, it is very well presented and a helpful motivator. Now he needs to write a book "How to Get to the Gym".
It's a good system it's just that most of the book is about how he applied it to his own purposes so unless your desire to learn the exact same things he taught himself you're only going to find the first 2 chapters useful.
"You don't find time, you make it"
The emotional barrier is what you need to break in order to acquire any skill you want to proficiency, all it takes is motivation and practice. This book will provide the motivation, you provide the practice.