How can you turn down a book with a title like that?
My wife gave me this book when I started asking lots of questions about how music works. And for me, who's sung a lot of music but has never had formal training or education in it, it was wonderful on two levels.
On the teaching/pedagogical level, the author Gerald Eskelin is a big proponent of letting students hear sounds first, learn notation second. This is a lot like what my physics colleagues do in the classroom (and what I try to do when possible): let the students experiment and observe, and then and only then teach the theory behind what happened. Students learn better by experiencing it, by singing and relating notes to each other.
On the abstract/theory level, Eskelin shows how there is a "natural", innate music that is based on the fractions that relate notes to each other. This music is best expressed by the major/minor scales because it fits those fractions best. How this works in music is that sounds made from flexible strings can tune better than sounds made my fixed machines (pianos, fretted guitars, etc.). So the piano is only an approximation of "true" tuning and true harmonies .There is a native music to the world (and pianos only approximate it!). And when this music is in tune everything just "pops" together.
I think this is important on pretty much every level. On the choir-singer level, it reminds me of just this Christmastime when we were learning "Rejoice, Rejoice" by Philip Stopford (a.k.a. "the best young choral composer out there right now"). Stopford has the basses sing a melody all alone that suddenly jumps up at the end to a C-sharp. It's strange to hear and practice by itself, but when we were singing "without a net" for the first time (that is, without our lovely and talented pianist (whom I'm married to) playing along), we jumped right up to that C-sharp and I suddenly felt uncertain ... because it DIDN'T feel weird! The reason is that note fits into the music and when you hit it you land right where you relate to the rest of the music and despite the strangeness of the interval, it just feels right. Good music fits together right, and there is a "best" way to do it.
In any case, this is a wonderful book and worth reading if you're interested in how music works, no matter your background, teachers and students. (I'm kind of glad I didn't know the "lies" -- it made it easier to learn the true way music fits together.)