...and on the subject of annoying/frustrating, what about those charming people who thank you for giving way at night by flashing their headlights at point blank range, destroying your night vision and searing your retinas. Is it really beyond their wits to briefly turn headlights down then up again instead of flashing main beam?
Highway code:
Rule 114
You MUST NOT
use any lights in a way which would dazzle or cause discomfort to other road users, including pedestrians, cyclists and horse riders
Flashing headlights gradually became normal behaviour for many motorists after lorry drivers started flashing each other when overtaking and pulling back in etc. In fact a headlight flash should be used as a warning of your presence.
The Highway Code states, "Only flash your headlights to let other road users know that you are there. Do not flash your headlights to convey any other message or intimidate other road users."
I was always taught to use headlights as a warning when sounding the horn was impracticable, such as on motorways and other fast roads...and at night during the quiet hours. Unfortunately, because it has become normal practice to use headlights as an 'after you' signal, giving a headlight flash as a warning can often be misinterpreted with catastrophic results.