I got in a huge argument over this in the days of Usenet, before the web. Casino Verite (if you don't pick the real shuffle options) doesn't shuffle at all. Instead, it randomly selects cards from the shoe. This allows easy implementation of biases. So, you can program the cards to present unusually high counts, low counts, multi-card hands, difficult hands, hands you have had difficulty with in the past, etc., by randomly rejecting cards and placing them back in the shoe if they don't fit the bias settings. In practice, I believe this is very important. Otherwise, you spend most of your time practicing the same, trivial, boring, simplistic decisions over and over. The point is to dramatically reduce the amount of practice time needed by making certain that you are presented with more difficult situations, more often than you would be in real life. Otherwise, you would spend most of your practice time looking at absurdly obvious hands like TTvT, the most common hand by far.