I've been the guy that's gone mental before, but with justification.
Driving from Greenock to Glasgow around 5pm approaching the turn off for the Erskine bridge. There was an incident on the bridge as the traffic was tailed back off the slip road onto the M8 and went down the M8 for a distance in the NSL. I'm not taking that junction anyway so I slow down to about 30mph and move into the outside lane to overtake.
So I'm cruising along when all of a sudden a car pulls out from the NSL into the outside lane. I brake and keep a couple of car lengths between us thinking he's had enough of queuing and he's decided to miss the junction. Instead he's just decided he doesn't want me to get past as he's keeping pace with the traffic in the NSL. So I close the gap a little bit but the guy refuses to move in. I didn't bother flashing my lights or anything and I just thought bugger it and I moved back into the NSL. He does the same so I pull out to overtake and as I'm about to pass him he swerves again but this time I'm alongside him so I have to slam the brakes on and swerve onto the central reservation narrowly avoiding the barrier and again he's blocking me to stop me overtaking as though anyone that overtakes is trying to jump the queue rather than simply go past the junction with the problem.
That was the point I lost my temper and started screaming every obscenity under the sun at him threating every single one of his living family members. 😳