That is a fantastic book. It was very much written for magicians and gives away many of Derren Brown's famous routines so reader beware!
The aspects of showmanship and performance really stuck with me. I often remember snippets of the book even today.
One of my favourite stories is when Derren is having dinner with friends and their child says "Show me a magic trick!" So Derren asks the child to name a card. He then flips over, by pure coincidence, the card the child named. Of course, he was planning on doing a more elaborate routine but he was present enough to notice that he would not be able to top his accidental trick and put the cards away.
He talks a lot about taking risks in performance and being attentive to the energy in the room. Of course, you need some solid reliable tricks as well to back this up!