Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Bankers have only 1 Secret?

Disappointed, this book does discuss paying your mortgage off early and gives you the technique to accomplish that, but a whole book for this one technique? I wouldn't purchase it again, skim it at the bookstore. Discuss the method the book gives with your mortgage holder - some won't apply your money in the way the book notes. They don't have to, if you signed a paper at closing in which the bank stated a different method of applying your extra money. Remember that stack of papers you signed, look through them and see if there is one that shows how the bank will apply extra payments, even ones marked principle only.