If you think you have a shot on an enemy (even if it was a 1v1), check behind you. Historically, there was a possibility of having a bandit there, in the MA someone will be there, guaranteed.
If you are in anything but a Spit or a 51 multiply that by 3, since most are tired of shooting down the same planes. If you are in a P38, assume that every bandit within 5.9k will be diving on you.