This is where I stayed this weekend.

Mali, the dog is not anymore, sadly. This is actually an old picture.
I am very lucky that my father was there when I was young and living in Zambia and learning for my license. Roads were not crowded in the mid sixties.
He stressed that in order to overtake safely it is important to stay well back for 3 reasons.
This dangerous behaviour is so common it is unbelievable!
Most people will have had some kind of instruction before they received their license, except for those (assume nothing) who have bribed or bought it one way or another.
If they took a test to get their license – it is a reasonable expectation that all road code books tell the student to leave enough stopping lengths according to the speed of both vehicles. Logically, to spell it out – this is in case the car in front brakes suddenly (kangaroo, oncoming truck the other side of the road).