I always try to call every shot as best as I can. If I didn't see it completely out, I'll play it. If it was completely out, I'll call it. I rarely argue with opponents on out calls, the most I've said in response to a bad call is "are you sure?"
You never know when you're going to get a total a-hole on the other side who would chase you down and beat you with his racquet.
Bullfan, "Bull rap, there is video evidence." and "Dude it's on the Internet, and hasn't been hidden."