Now let’s talk about the shuffle itself. Suppose you are playing in a four deck game (five, six or more decks are analogous). When the hand is over, the dealer stacks the discards at the side of the table. Eventually, she will stop dealing and place the undealt portion of the shoe on top of the discard stack. Then she will divide the four-deck stack into two two-deck stacks. The first consists of the first two decks of discards, while the second consists of the remaining discards with the undealt portion on top.
Next the deal will take apportion off the top of each stack shuffle them together, and place them in a new stack. This process is continued until the two original two-deck stacks are exhausted and a new intermingled stack is created. However, the newly shuffled stack in only intermingled by the “paired” pieces. A particular card will always be located inside of a two-piece interval.
However, the newly shuffled stack is only intermingled by the paired paces. A particular card will always be located inside of a two-piece interval. Consequently, this shuffle which I will call a “single shuffle'” is a non-random shuffle. (Of course, it is not always done in this way. But this information should aid the reader in recognizing a non-random shuffle.)
Now, let’s examine another type of shuffle. It is identical to single shuffle, with one exception: The two two-deck stacks are first shuffled within themselves. In other words, each stack is split into two one deck intervals, these two decks are intermingled with each other, the two-deck tacks are then recreated, and then the previously explained shuffling procedure is started and completed.
Now the location of a particular card cannot be identified since the first shuffle will place it somewhere (unknown) in the two-deck stack. Consequently, this shuffle, which I will call a “double shuffle” is a random shuffle and nullifies the method that will be described in the next blog.