Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Important if True

For me, the book does not read nearly as well as the associated promotional literature. Much of the book seems to me or strikes me as a plenitude of powerless platitudes. It all seems that it should be very nice if it actually works. For some person who somehow gets it to work properly, I'm sure it would be life-changing and very important. My own experience doesn't suggest very well how it actually could work---at all. If the book were actually as good as its promotional literature....