Something I don't understand about deep astonishment: If the climax of the trick is showing them their magic word on the cards,what is the point in having them cut a card and placing it under the wallet?

I think its meant to be a surprise. The person thinks your just gonna pull his card off the top of teh deck. So when you lay the cards down it comes as even more of a surprise.

It says in the desciption that you use there magic word to find your card. I don't know what this means and they write it really small its easy to miss.

The reason that you have the person pick a card serves 2 purposes, if you want to know them then post a message in the Penguin's Only forums & I'll answer it, I don't want to give away anything.