Effective, informative book
I purchased this book not for use as an interviewee, but an interviewer. I wanted to learn better ways to meet with potential employees and assess their potential. I learned that, as well as seeing the positive, thoughtful answers can be a benefit to any business interaction, as well as personal interactions. From that standpoint, it's an excellent, effective book.
That said, if I interviewed someone and all of their answers were this polished, they would seem almost too perfect for the job. This would leave me wondering where and when the fatal flaw would appear, and actually hesitate to hire them over someone with strong, but not 100% perfect answers. As with all of life, balance is key.