All Sales Strategy/improvement courses/books are very simple. The problem is that 90% of sales people don't pick up a book in any given year to improve their performance and, of the other 10% who read a book or do something to try and improve their sales results, 90% of them fail to apply what they have learned on a consistent basis.
That means that 99% of people fail to improve their results via books/courses!
Having said that I absolutely enjoyed this book because of is its simplicity, written in true "little book" form. I really like these books as they are quick reads by cutting through 90% of the (...).
They key to getting long-term value out of a book like this is to practice what you read. I know that when I was applying various techniques I learned in the past my results went up on a consistent basis so I am going back to the books and applying the techniques/skills on a more consistent manner.
Whether you like it or not you are selling everyday. You are selling yourself regardless of what you do for a living. You sell yourself to your family, friends, co-workers, etc. You are creating an image in that person's mind of what they associate you with (pain or pleasure).
Another insightful book on sales is How to be a Rainmaker, by Jeffrey Fox and Successful Selling by Brian Tracy.