Bullshit.........an eye for an eye............you hit me, I hit you.........simples
And if they pull a knife which is highly possible????
I never react to people when I'm driving as I feel it won't get me anywhere. They cut you up, ok, it pisses you off but everyone makes mistakes and what do you gain from shouting and searing at them?
If people are being dangerous then I usually stay well away as they are unpredictable. If you really don't like it then call the police and report them. Chances are it will be added to their file. They might get a word in their ear.....