I don't remember when last time someone passing me upset me ... but it's always the people who shouldn't drive in winter (because they can barely drive when it rains ...) driving so slow, that it's almost to the point of stalling going through a turn. I think they somewhere deep down believe that the car can flip on its roof, or that they will do 360 the moment they start turning .... unbelievably frustrating. It's an art to stay calm ... LOL
A corolla yesterday slowed down to <10 km/h to make a right turn at an intersection, then sped up to 40 km/h on the straight (in a 70). It's the same as stupid people on bikes, if the fastest you can safely turn is 50 km/h, maybe you shouldn't be doing 250 between the corners.