The explanation for a dumper is that it was a very high positive count and the dealer was actually busting when they were supposed to. For every dumper story for an AP with experience, there is the opposite experience of getting murdered in very high counts. Player 11 vs. dealer's 6. Player doubles, gets an Ace. Dealer turns over a 7 for then a 2, then an ace, then another ace. And then in another shoe, you're sitting out because the count is very negative and the players are winning every hand as they progress their bets up and the dealer breaks every hand. Over the long run, APs have a very small advantage and grind out their wins. Or maybe it's the movie 21 where the team wins every big bet because the count is positive.