Some thoughts on the "Flashing a Passing Caravan" thread. By all means 'flash in' overtaking 'vans and lorries though it seems many foreign drivers - and some home grown - are unaware of the meaning of this courtesy. In many countries flashing means 'get out of my way - I AM COMING THROUGH!' A further problem is if others mistake your meaning. I have seen the situation where someone flashed a friend passing in the opposite direction and a car waiting in a side road took this to be an invitation to join the stream of traffic. The resulting chaos delayed the ambulance!