Having said what I did earlier I will say there are those drivers/riders where even the most innocuous of body language seems to send them into a rage.
This summer I went out to
Hamble to research a local off-road route. Coming back there is a
traffic island and I usually shoulder check before I get there and move into primary. Doing so on that afternoon I noticed a 4x4 behind me at distance. As I entered the pinch point it felt wrong, I dont remember if I'd heard a sound or something (my hearing isnt the best) but I looked around in time to see the 4x4 suddenly slamming the brakes on and sliding to a stop near my right rear-side.
I didnt swear. I didnt give the guy the bird. I just swerved left and shook my head maybe twice and blew out some air in that kind of relief I'm sure everyone feels in such situations where something bad is narrowly missed.
The road widened. Heard the driver crunch his gears and pull parallel with the passenger window where the driver shouts "Why did you shake your f***ing head at me??!!"
"You scared the s*** out of me. I thought you were going to rear-end me." The only time I recall swearing and it was in response.
He then drove off at speed, well above the limit, and muttering something now garbled but sweary...