I had a guy behind me the other day (in Merc as well) who was clearly frantic that I had the audacity to stick to the 30 limit (residential area, kids about) and then the downright cheek to obey the subsequent 20 limit through the main village.
Driving an inch off my bumper, red face, doing the above mentioned “wasp in the car” act. Usual stuff. I just left him too it.
Then as we go to the end of the 20 section (which is only half a mile long) he decided to floor it and overtake me at speed on the wrong side of a traffic island!?
Naturally there was a car coming the other way. I slammed on the brakes, as did the oncoming car, giving him just enough room to pass the island and swerve back across with literally inches to spare and then zoom off.
I have no doubt that in his mind that whole incident was entirely my fault.
TL;DR; some people drive like utter bellends and it’s never their fault.