Leaving explains it pretty well.
For me, CCMC helps a former member like me to understand exactly what was done to me by the Borg and how they did it. What is impressive, as Leaving says, is that the book is about cults in general and has many examples, NONE of which are JWs but ALL of which reflect Watchtower practices in some way.
Knowing what they do to members and recruits, to me, helps me to understand what happened to me and prevent it from ever happening again, as well as equipping me to help others.