I own the book. It's meaning to me has kind of evolved as time has gone on. I see it as "poor mans Advaita"...not that that's bad. Robert reaches an audience that perhaps Advaita doesn't.
The Books terminology is a little hokey for my tastes; irrevelant.
I'd just as soon read "I am that" and skip all the terminology.
Anyway, there's a new Documentary called "leap" featuring interviews with people who feel the world is an Illusion. Robert has some time in that film.
clips:
YouTube - Robert Scheinfeld in Leap! The Documentary #3