Shuffling cards is a challenging task. It is the one part of the game where we humans directly interact with the randomness of the hands that follow. A hand shuffle never fully randomizes the cards. However, if enough goes right with the shuffle, then it can be considered random enough to effectively defeat shuffle-based advantage play. On the other hand, various steps, if either omitted or not completed in a safe manner, open up huge gaps in game protection. Methods of advantage play that attack the shuffle include shuffle tracking, Ace sequencing, edge sorting and location play.

The following video demonstrates five common shuffle procedures. It also briefly describes the purpose of each step. Missing is the "plug" - which is a typical step in a shoe-game shuffle that helps prevent certain types of shuffle tracking. Also, I don't describe a "box" in this video - a "strip" and "box" are essentially the same thing.

The second part of the video gives a sample bad shuffle, where the strip is placed at the start of the shuffle procedure. In it, I sequence the Ace of Clubs using the Queen and King of Clubs as key cards. You would think that strip ⇒ riffle ⇒ riffle ⇒ turn ⇒ riffle ⇒ cut would be safe, wouldn't you? Wrong. A much stronger shuffle is riffle ⇒ riffle ⇒ strip ⇒ turn ⇒ riffle.

It seems a bit crazy to be making a video like this. But, both Crockfords and Borgata didn't include a turn in their shuffles. Casinos throughout the country are being beaten by Ace sequencing teams because they don't include a strip in their shuffle. Skilled cutting allows players to put an observed card into a known location. Many casinos obsess over riffles at the expense of other necessary parts of the shuffle. You will see some casinos require both a riffle and strip before putting the cards into an automatic shuffler, while not including a turn. In other words, as easy as this video appears, it is surprising to me how misunderstood these elements are, and how often the shuffle is the point of vulnerability that advantage players target.
 

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received his Ph.D. in Mathematics from the University of Arizona in 1983. Eliot has been a Professor of both Mathematics and Computer Science. Eliot retired from academia in 2009. Eliot Jacobson