Flash hazard lights to say "thank you"

[jack]

For a while, I've noticed cars flashing both indicators simultaneously (presumably by turning hazard lights on then off again) to say "thank you" for letting them in.

I think I first noticed it by lorries -- google suggests it may have been a lorry driver custom first.

I really like the idea of being able to say "thank you" or "sorry" as well as "please" or "get out of my way" when driving.

Am I right that it's new, or did I just not notice when I started driving?

Presumably it's not allowed (just like flashing headlights to say "excuse me" or "after you" or "do you know your lights are on/there's something wrong with your car/etc" was never an authorised use according to the highway code). Is it a bad idea, or not?

Comments

[onyxlynx]

On your motorways, right? Not in town?

I noticed the flashing lights when I drove across the USA the first time ('75). It was a code among the long-distance truckers (lorryists?) who, I have to say, have impressive flash capabilities and it meant that it was much safer to drive at night.

As far as I can tell, these signals are not used in heavily populated areas. So you may not have seen it until you were driving for distance.