I call my opponent for a foot fault whenever I'm undecided on whether or not his serve was in. I also do it randomly just to keep him on his toes. Don't want him getting too comfortable out there or thinking I am going to play Naive Ned if he does decide to cheat.
It's a competitive tennis match. I'm not there to make friends. I'm there to win. Period.
Bills looking good, will win Super Bowl.