It explicitly teaches the METHOD to 2 magic tricks.
It also explicitly teaches the METHOD to cold reading.
It ALSO teaches explicitly the METHOD to hypnotise people.
The book explicitly teaches the METHOD to retain information for much, much longer. Even if you don't use it to do magic (you could) you can still apply it to other spheres of your life. I'm pretty sure you don't ONLY perform magic (?).
But the book's importance is implicit. It teaches how to make a coin vanish, but the book's advice will take it from 0 to insanely good. The book teaches about the mentality one needs to have to perform, and to perform well.
In short, remember this :- I myself, and many other people, gauge a magician's ''coolness'' or ''charmingness'' or ''market value'' by how well they can hold people's attention and appeal to them WITHOUT magic. If somebody is amazing when doing magic, but you take away their cards and coins and sponge balls and ropes for them, and then they are reduced to uninteresting, boring people tiring to have conversations with, such people are not good enough performing magicians for me. This book will teach you how to retain the 'power' even without constantly asking your friends to pick a card. This book is gold (even more valuable than another book written by Derren, the Confessions of a Conjuror, in my opinion).