in such situations, the best thing to do is to act dumb, stop
the car, get off, and ask the other diver politely what seems to be
the matter. their aggressive behaviour are meant to agitate so when
you keep your cool no matter what and better yet raise their blood
pressure up a notch or two more while doing so, there's no doubt
who the winner is 
just imagine the entertainment and satisfaction i got when the poor
bastard is screaming his head off and popping blood vessels and all
he got was a blur sotong look from me and a 'huh? what?' you should
try it someday!
