... The negatives canceling each other out makes more sense as players could both get way into the negative and prolong a game indefinitely. They still have a tournament to run in a timely fashion.
In one Scott Frost game, I think there were 12 coins on the rail at one point, not all Scott's. Scott won. He seems to be the player most likely to intentional, and since he can run the balls well, it works for him.
As for timely at DCC, I think the record was a match between Darren Appleton and Tom Spencer (a well-known 1970s-80s player, GF column
). Darren was supposed to play in one of the TV table ring games, but had to finish his one pocket match with Spencer. He was leading 2-0 and ahead in the final game. He thought he would make the start time. Appleton lost the match 2-3 about six hours later. The match took 7.5 hours, IIRC.
Chess clock is my answer.