happens to most people I think, chased some twat for 30 miles once round and round, he eventually drove to a police station and started blasting his horn outside, soft twat. He cut in front of me at a 2 lane into 1 road and I had to move into the entrance to a side street to avoid damage, obviously flashed him and he started gesturing at me, thats it, proper flipped and the red mist came down. Too easy done and looking back it is wrong.
Remember watching a program about it once and it said to imagine you were on foot and someone walked in front of you causing you to slow down, you never get tools out and threaten them or gesture at them you just make whatever adjustments are necassery i.e. slow down or move to the side. In cars in your own little bubble you think your invincible and thats where the problems start.