asshat in a benz

if you see a 50ish dude with graying dark hair driving a black 2005/6 mercedes-benz s500 4matic with dealer plates DL 46 S - hit him. yesterday i was out on my bike with my riding partner, dave. we come cruising down a hill and around a curve and see this worthless excuse for a human being going very very slowly. we swing out to the right of him to pass him and he rolls down his windown and makes some remark about the speed limit being only 15. after this we come up to a hill which causes us to drop back behind him. upon cresting the hill and starting our decent, we start picking up speed and close back in on him. well this jackass hits his brakes causing dave, my riding partner to swerve and barely miss. i was far enough back where i was on my brakes and stopped in plenty of space. the piece of garbage then hits the gas and speeds up. we, still being nearly at the top of the hill are really starting to pick up speed and we make our second move at passing him. Dave is in front and this cock-smoke swerves into him. and not just a little head-fake swerve. he completely switches lanes. now unlike myself dave is a pretty accomplished cyclist and manages to once again, avoid getting hit. i'll be damned if i can figure out how though.
this is getting very dangerous now and we both get on it to catch up to the guy to curse at him a bit. by this point, we've crested another hill and are again, on our way back down so we got gravity working for us. dave is one fast mofo and is about 10 yards ahead of me and he is all of 2 yards back from the benz. this asshat slams on his brakes screeching his tires and this time, dave isn't so lucky. he tries to swerve but catches the rear left corner of the car and takes a nasty spill in the road. jackass speeds off and a car behind us who had witnessed the whole thing takes off to catch up to him but doesn't truly succeed in getting him to stop. the benz eventually makes a uturn and is coming back towards us. as he is coming down the road he makes a little turn faking that he is going to swerve strait into us. this scares me shitless as my feet are still firmly strapped into my pedals and i have zero sideways mobility. well, he turns back and rolls down his window to yell at us, "i told you not to tailgate!" dude, what the fuck? he decides to try make dave crash on 3 separate occasions and this is our fault? asshole is not nearly a strong enough word to describe this guy.