While I have your attention

[Texas Aggie]

The MF rule is basically there to keep in your pocket and pull it out when it can be used effectively. When? Good question. One situation might be late in the game where a team too far behind to do any good is still fouling (2 or more players involved, obviously) and the team they are fouling is not in the bonus. If you are concerned about player safety, you might call a MF, put the player on the line, and move on. Another situation might be a fight that breaks out during a live ball. You can judge a flagrant MF on 2 players and throw them both out.

I've never called one either and I can't think of too many situations where an intentional or flagrant foul might not be better.