I'd never heard of "edge sorting" prior to this comment, but reading the Wikipedia entry for it, it strikes me that the technique relies entirely on the cooperation of the croupier/dealer coupled with inconsistent printing/cutting of the pattern on the rear of the card?

I've not spent a lot of time in casinos, but I am surprised that given the technique is apparently widely known, dealers are not more reluctant to accede to player's requests to rotate a card for "luck" or "superstition", or whatever other rhetorical device is used to convince.

It also seems like simply taking care in the production of the cards and their backing design would afford a significant degree of preventative protection too. Sure it might drive the cost of a pack of cards up given the extra precision needed when printing and cutting the cards, but this does not seem beyond the resources of a casino.

I'd love to see footage of how Ivey manipulating the dealer into rotating cards unfolded.