>>5912648It teaches you how to simplify studies, isolate certain fundamentals, in which you can apply to bigger pieces.
the "map" aspect of it is not the a-z "I don't gotta look anywhere else" more giving you more tools to use in your tool belt.
He doesn't go over perspective at all from what I've skimmed through (he does tell you to learn it to get the other eye). I think it just covers portraits not anatomy, etc.
It's easy for someone at any level to jump into (If you can draw the basic shapes, which he does go over). It's not going to fix you over night like those pictures promoting it, you'll have to put in reps of the exercises. Take your time with it, they're good exercises to get the hang of.