First, let's make it perfectly clear that we're discussing something that happened 20 years ago. No one is suggesting that JA Nugget is cheating today.

Back in the days when the casinos were still being run by the mob, it was indeed not uncommon for each one to employ a "bust-out" dealer or two. He/she was a skilled card mechanic who would quickly relieve an AP of his/her bankroll, or even someone who was simply enjoying a hot streak. In Beat the Dealer, Professor Thorp described widespread casino cheating.

However, while I never completely rule out the possibility of dealer cheating, it has largely gone the way of S17 single deck games dealt to the last few cards.

Preferential shuffling is a different matter entirely. While this had been widely discussed, and many AP's consider it to be a form of casino cheating, courts in Nevada and elsewhere have generally ruled it to be perfectly legal. It is not uncommon, especially in games in which no cut card is used.