I think it is out job to know as much about the game as possible. For example I called two carry/palming calls last Friday and the coach tried to imply that I called more than anyone else. My response was to him, "We have called 5 (palming) calls in this first half, and I called the last two." I did not hear much of anything from him after that.
If you know it better prepares you for if and when you call that 5th foul you are prepare to handle it. Also I feel that you should not change what you do, but you should be aware. Because that 5th foul better be good or this might be one of the plays they send to the supervisor. I would like the foul to be there, but then again, kids foul out all the time and I was not aware of this. I guess it really depends on who the player is that has the 4th foul and what his coach thinks of that kid.
Peace