I understand the common games tie breaker between division teams but what if Team A has played Team C twice (one loss, one win) and Team B has played Team C only once and won? Would Team A's pct = .500 while Team B's pct = 1.000 ? Do I count both games for Team A or only one (and if so, which one?) Thanks!
You don't specify which sport or league you're interested in, but I'm assuming it's the NFL since I know that's a criterion used there. If that's the case then by the NFL's tiebreaking procedure, they use the "best won-lost-tied percentage in common games." For your example, Team B would then win the tie-breaker. I think this makes perfect sense, too, and would expect to see the same method used for any other league that uses this criterion.