The situation is that sometimes strictly following the rules is more dangerous than breaking them. This is because rules in Bulgaria are not made to protect you, they are a way to avoid responsibility. Actually, if you dig into it, you will notice that almost every rule in Bulgaria is designed not to be a guideline, but to be something like a "disclaimer".
What do I mean - a speed limit at a dangerous curve rather than redesigning the curve to make it safe, a speed limit because of bad road rather than repairing the road...
Generally, a traffic sign does not mean "DO NOT SPEED", it means "I am not assuming responsibility if you kill someone here, regardless of the fact that it's my job to make the road safe. It's safe - there is a speed limit and you will die because you are driving at 90 in the middle of nowhere, not because I am lazy and I did not repair the road".
So, having the disclaimer type of rules teaches you that you don't have to follow the rules in order to be safe. If I see a speed limit of 40 on a German Autobahn, I will slow down because there is probably a very good reason for this, not because I am afraid of a fine. On the other hand, if I see a speed limit of 40 on a Bulgarian road, I will just assume that either there is a junction or there were construction works 3 years and no one removed the sign. So you drive at 90, you slow down because there is a junction, then you accelerate again and in a kilometer comes the next junction. I even developed a rule of thumb for speed limits in Bulgaria that are to be obeyed - if you are driving in a hilly region and you see an old rusty sign, you'd better obey it.
This, combined with the almost zero control and enforcement of rules makes the situation quite interesting :)
Furthermore, Sofia traffic is crazy.