I have a teammate who plays singles. In at least 50% of her matches, there is a scoring dispute. These are not little scoring disputes. They are "Walk Up To The Net With Hands On Hips" scoring disputes. One dispute was at a second set changeover; upon resumption of play she believed the score was 1-2 and opponent said 1-4. Another time the problem was 15-30 or ad-out. She says the problem usually happens in her opponents' service games, as she announces the score clearly when she serves but most opponents mumble. Anyway, I play doubles, so it is rare to have a major scoring dispute because you have four people keeping track of the score. How often do singles players experience a scoring dispute, and what sorts of things can be done to prevent them?