A plays B twice.
IF ONE PLAYER (say A) WINS TWICE, A plays C twice.
   IF A WINS TWICE, B plays C
     the winner plays A 3 times and has to win them all.
   IF A WINS 1 GAME, A plays C best-of-4 (A wins ties)
   IF A LOSES TWICE, A plays C again.
      IF A WINS, A plays C best-of-3
      IF C WINS, B plays C 3 times, and B has to win all 3.
IF BOTH WIN 1 GAME,
   A and B play again (say A wins).  A plays C twice.
   IF A WINS TWICE, A plays B, and B has to win all 3.
   IF A WINS 1 GAME, A plays C best-of-3
   IF A LOSES TWICE, A plays B
      the winner plays C twice (C wins ties)