Ed De Bono's works are packed with useful tools and insights. Because they are packed, gaining the most benefit requires reading "between the lines". I believe the listener must "stop the tape" (or put down the book) and make the effort to expand on De Bono's concepts and comments, in part by mapping them into past personal experiences (particularly useful are those experiences that had costly or unpleasant outcomes for the listener because at the time he/she lacked (or misapplied) certain thinking tools).
I am convinced that anyone of average intelligence and education who invests about 20 hours effort to listen to, internalize, and then practice a half-dozen of De Bono's various thinking tools will be amazed at the improvement it will yield in his/her relationships and work. I offer this comment as neither a religious nor "New Age" promoter but merely as a person who continues to benefit from these approaches.
I also highly recommend De Bono's "Teach Your Child to Think" tapes. They largely complement this set.