Only at office casino night party
At one point, the dealer was down to his last card, and the player to my right was mulling over hitting a 15. Since the count was -1, I guaranteed her the last card was 6 or less.
Since after the last card came, the discard pile was shuffled and play continued from there, one had to quickly count the cards on the table to get the correct running count. I soon learned that all one had to do was to negate the running count before the beginning of the last round.