It is hard enough to prove that there is a card mechanic at work unless you have hidden cameras on the premises in some fancy casino; and then even, you could not be able to see the movements. But if the mechanic detects agitation, he will probably decide to put his tricks away until another day.
Palming a card during the reordering is the trick of the classic mechanic. If you think that they are only made by hockey magicians to the benefits of ladies’ aid or children’s birthday parties, stay away from card games.
On the other hand, palming is a particularly dangerous trick because you run the risk of being interfered with the test, well, in your palm. The dealer prevents from entering a good card by letting it rest in the palm of his hand as he shuffles, then slips it into his hand as he shuffles, then slips it into his hand during the deal.
More specialized are techniques (such as riffle-stacking) that depend on the speed of the paper manipulator, counting the skill and touch with precision developed.
Good cards are pre-identified by the shuffler, then slipped into the platform in whatever order and position they want. Thus, the dealer will know that the fourth, seventh, sixteenth and twenty-first cards are aces and will know who is holding them, even if he is not himself.
Of course, he can handle all four axes to himself, if he wishes to, giving them positions in the platforms that correspond to his turn to business.
Another highly successful mixed fraud is the counterfeit-overhand reordering. Since this movement is so easy for an expert to perform and so difficult to detect, most good card players insist on classic shuffling with both halves of the deck down on the table.
In the environmental shuffle, the cards are held in the dealer’s hand and inserted into the other hand, allegedly intertwining them in the process. The mechanic can simply hold the desired card on the top or bottom of the platform feeling where that card is and not letting it braid until the end of the reordering.
However, just because a dealer puts the deck down on the shuffle table does not mean it’s honest. Half-push-through, for example, just as the name suggests, two of the deck, while the shuffle seems to be joining it, are actually pushed upward through each other and wind as two separate halves again, organized, just as they were before.
The dealer seems to push the platform together after a shuffle but then cut the cards by dividing the two halves that are keeping secretly separate all along.
If you were sitting behind the dealer you would see the two halves of the intertwined platform, but not aligned, with some of the cards protruding at a deep angle to the others. In the casinos, from where the players sit, however, the platform seems square.