I purchased this book because an animator I follow recommended it. The book is overpriced, presumably because it has a companion app that is supposed to pull up drawing videos while you are reading it. When I purchased this book in 2021 the app did not work. I saw on the author's website that people outside of the USA (who can't get the app) could email a photo of them holding the book to unlock the same videos on the author's website, so I sent in a photo of me with the book, and the author kindly unlocked the videos for me.
All of that hassle aside, I did not connect with this book. I carefully read every page and watched all the videos on my computer and still could not tell you with any confidence what the difference is between applied and directional FORCE (the word "force" is capitalized every time it appears in this book....). This is perhaps due to my own inability to wrap my head around the various analogies provided (skiing around the figure, driving around the figure, riding a rollercoaster, etc), or just the fact that I was unable to put these ideas into practice (i.e. drawing from the figure) while I was reading it during the pandemic. But I believe there was room for greater clarity in the explanations and examples, especially in a book that has been in print for 10+ years.