I have seen a pit person checking the machine. He took 3 cards out, face down, put the remaining 6 decks in and after the shuffle came to a stop, he read from the window on top, the cards he had taken out, and then confirmed that the reading was accurate, the machine could read the missing cards.
This tells me that the machine could be programmed, if nothing else, to clump big and small cards together. Whether they do it or not is subject to debate.
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