Interesting and I would agree with you on that. I think the non-randomness results in more severe streaks than a random deck also. I would think the 10's tend to get grouped together in the discard rack and may not be randomly split apart in the shuffle. It seems like when a deck gets sour it can stay sour for a long time and vice versa but hard to prove any of that. One thing I've always wanted to track in real life is how often the dealer busts showing an Ace. Theoretically the dealer busts only about 20% of the time showing an Ace, but it seems he busts at a higher rate, drawing a 10-10 more often than he should.
If anybody knows of a true shuffle routine, we would be interested.