Derren Brown never tells us how he pulled off all of those tricks. All he tells us is that he doesn't have any psychic ability but he is going to convince various people of various belief systems of his ability using some kind of tricks. All he says is that the tricks are written in books but he doesn't tell us which books. Unless he tells us how he did it, we are going to have to believe that he has supernatural abilities.

If he doesn't have "supernatural" abilities, it is clear that he is a very gifted person anyway.