What I got from it that you get problems if you advance far enough and then don't keep going. The benefit claimed in the first part of the series is having a permanently clearer sense of your thinking process, whatever that means exactly.
I really prefer the 'this may mess you up if done wrong' meditation instruction to the usual sanitized new agey pap, purely on aesthetic level. It makes meditation sound like something that can actually be effective. Like a scalpel instead of a homeopathic solution.
