fyi;
double lines in Thailand are the way the thais find their way home

In Bangladesh, the lines on a 3 lane highway/motorway were used by the locals to provide guidance for a 5 lane traffic flow, plus an overtaking margin-

3 lanes of traffic, roughly tracking down between the lines.
2 lanes of traffic religiously tracking the nicely painted lines, tuk tuks with their front wheel, cars straddling the line.
The overtaking lane was wherever they bloody felt like, so long as there was nothing in the way. (Soft squidgy things like people don’t count) Often, the gap in the barrier separating opposite direction traffic providing access to the lower density opposite carriageway would facilitate overtaking and a random increase in the number of available lanes.
Traffic lights existed to control the speed of traffic- green for go, amber having often been stolen, and red for go faster.

Sleeping policemen/speed bumps/traffic calming ridges were used to arrest vehicle speeds. Especially useful with 70/80kph traffic whose suspension ceased being so about 30 years, or several hundred kilos of welded on repairs prior.
Policemen with stout sticks being the final part of the puzzle, taking aim at any exposed head travelling at under 30kph.

There were road laws written down, but I guess these are largely irrelevant when a very significant proportion of the drivers can’t read to do any learning, and the rich bastards aren’t going to give a damn, anyway.

There seems to be some commonality...

Don't do them lines.