We have 2 types of drivers here in rural Isaan.
Turtle slow and wide open.
The turtle slow drivers are those that stay under 30km/hr on the highway.
The only thing you can do is wait and pass safely.
The other drivers are the wide open drivers.
Since there are no police cars patrolling where we live, some drivers just drive at ridiculously high speeds.
They will come up and tailgate you, then pass you even on the blind corners not knowing if oncoming traffic is coming or not.
You have to be very aware of these wide open drivers and sometimes slow or even move out of the way.
It is just the behavior of these drivers here.
Best to just understand that this happens and let it go at that.
It is a very bad habit that is inbred in drivers here with no formal training.