I came across Bill's book after watching several of his excellent piano tutorial videos on his YouTube channel [...]).
It seemed that for a "pianist" of my calibre (i.e. one who is mainly self taught, fairly musical, can bang out a passable tune using chords and who knows a bit of theory - but is in no way a "proper" piano player) this book might be just the ticket. And indeed it is.
As another reviewer pointed out, you can use the book as a "standalone", but it's best when used alongside the YouTube channel, because it's great to see Bill demonstrating the things that the book is teaching, and it helps you to find out if your effort is remotely right! This is a really innovative way of enhancing the teaching aspects of the book, and works very well.
If you've never even touched a piano before, this may not be the book for you, but if you're passingly familiar with it and - like the subtitle suggests - you want to learn "the stuff your teacher never taught you", then you can't go wrong. My playing has improved no end - highly recommended.