This book is very comprehensive, it is clear that no one knows absolutely nothing of music theory should not rush it, because even if it starts with the basic way intervals, it is already too high for a complete novice.
For me it is a method which as said above is progressive, we share basic intervals until you reach mirroring, the resolution agreed, etc.
It is not the silver bullet, it does not exist, but it is quite possible to compose very well provided you have done all the exercises and even those beside such developing all modes 7 tones is a long time but it's enormously work!
As a former guitarist, we bathe me with the Greek modes (Ionian, Dorian, Phrygian, Lydian, Mixolydian, Aeolian, Locrian) Chinese except that when I ask how they worked one has ever been able to tell me, this book able to tell me and make me work, they no longer have any secrets or almost.