APTA changes to a twelve-point tie breaker
It didn’t take long before a committee consisting of tournament level players and headed by APTA President Bob Brown re-visited the nine-point tie-breaker adopted in early 1974.
The nine-point tie-breaker rule stated that if two teams reached 4-all the next point decided the set. This was considered unfair.
The APTA subsequently adopted a 12-point tie-breaker of its own, one in which the first team winning 7 points takes the set. If the teams reach 6-all then it takes a margin of two points to win (e.g. 8-6 or 12-10)
The sequence in the APTA 12-point tiebreaker is as follows:
Assume the last point of the set has ended, and the game score is 6-all. The players stay on the same side of the net and the next player in the regular service rotation serves once from the ad court.
When that point is over, the players change sides and the normal serving rotation continues with each player serving twice from the deuce court first and then the ad court.
After two players have served and the four points are over the teams change sides again and the other two competitors serve twice apiece in the normal service rotation.
This pattern is maintained through-out the remainder of the tie-breaker.
In this system, each player serves on the same side as he had been doing from the start of the set and do not have to contend with a new orientation to the winter sun.
This approach to the 12-point tie-breaker is unlike tennis where the first serve is from the deuce court and then each player serves from the ad court and then the deuce court. The teams also remain on one side for six consecutive points
Source: Platform Tennis Feb/Mar 1981