If I overtake left (left lane is free) and just drive a car behind the truck in front of me in the right lane, there is the danger that the car driver also pulls to overtake left without looking. If I blink with the main light when approaching, the car drivers often interpret me wrongly and think I will clear the way for them to overtake. So then they pull to left where I am giving gas. I could also overtake without a sign. Maybe even better, because this misunderstanding has already occurred par times. What do you say about it? Overtake with light horn, or without? Or is there a special way to act on the light horn that cannot be misunderstood?