What is taught in the book is how to understand, control, tame, direct, harness and cultivate attention, concentration and insight. It is an exceedingly meticulous yet very accessible and straightforward guide to getting the mind to stay on target and to see clearly thereby. The book is at once very traditional, being grounded in an old map and tradition, and yet very contemporary, being practical, at times scientific, and at all times helpful. There is nothing quite as detaled and thorough out there that I have seen to date.
He is sort of like Shinzen Young in ways, in his emphasis on being contemporary and non-sectarian, but he is yet a bit more traditional and vasly more thorough, sort of like the way the best 50's college-level electronics and practical chemistry textbooks are: they just get to the point clearly and keep doing that.
He doesn't wander or stray at all. He is not political. He has no apparent axes to grind. You will notice little of the personality of the author beyond his consistent clarity and desire to explain the exact mechanics and methods of what he is topic. The illustrations and diagrams are very helpful. I really think that the fundamental skills, terms, concepts and frameworks taught cut across meditative traditions, staying grounded in How To rather than some sectarian something. His blend of contemporary and traditional elements is fluid and easy, and never seems in tension but instead comes across as symbiotic and harmonious, reinforcing rather than contradictory.
Again, a remarkable work by a remarkable guy. I was lucky enough to meet him at the recent Dharma Teacher's convention in New York this June, and the maturity, depths and stability of his practice was clear.
