I didn't think it needed spelling out that they were saying "I read this book, I understood its message and was able to incorporate it into my life with notable results, so I am better at quitting or avoiding addictive behavior"
Rather than respond to you directly, I'll quote more from OP (a sly maneuver, I know):
> If that [Power of Habit book] was taught as a class in high school, it might eliminate long-term drug addiction.
No.
The book "Power of Habit", while incredibly valuable and informative, will not have this effect. If you believe otherwise, you have no understanding of the root causes of long-term addiction.
I didn't think it needed spelling out that they were saying "I read this book, I understood its message and was able to incorporate it into my life with notable results, so I am better at quitting or avoiding addictive behavior"