I took 6.001, and that's about how I remember it from back then. It's a great book but if you were going to lectures or willing to wrestle a bit with the problem sets, you didn't really have to touch the text. Sussman (as I recall) was a great prof, but one of the risks of having the book for the course written by the prof is that they may not be as objective about how well it's actually being used by students.