Was the deck placed on the table with a finger on top and then pressure slowly released? OR was it held in the hands?
The instructions state that the 'loaded' deck is placed on the table with the spectator pressing down on the deck with his/her finger.
You have to be mindful of the fact that the protruding end of the gaff will make a 'tell-tale' click if it strikes the edge of the deck at the wrong angle when replacing the right hand cards onto the selection. I think that this may be overcome by gluing a very small piece of cork on the protruding end of the gaff.