Cutting in front of somebody and locking up the brakes is a SERIOUS dick move...No matter what the circumstances. I had some asshole do that to me one time because I flashed my high beams on him when he ran a red light and cut me off. Needless to say it was raining out and I was doing 40mph. I came UNDER AN INCH of plowing his ass. If that would have happened I might be sitting in jail for manslaughter after I was through with him. Just my .02