The basic characteristic of a good driver and advanced drivers is that they are not lemmings. Everything they do is not from habit, or by rote or by ritual or by copying others.
Advanced drivers think about their driving continuously and every driver action is considered and for good a reason. Using that as a basic principle then, let's look at the use of dipped beam headlights in well lit streets:
Let's start by looking at the regulations with regard to use of headlamps:
Road Vehicles Lighting Regs 1989:
It is only an offence to drive at night, (during lighting up time) without Front Position Lamps on (We usually call them Side Lights) in 30 MPH Lit streets. It is not obligatory to use headlamps at all in 30MPH zones by virtue of a system of lit street lights. (Reg 25)
So in well lit 30 MPH areas, we are not required by law to have our headlights on at all.
Why do we think we should then?
Partly because of a very short road safety campaign (See & Be Seen) back in the 70s, like the seat belt Clunk Click campaign, but whereas no-one readily paid heed to the seat belt campaign, every-one seemed to think it a great idea to, needlessly, shine headlights at one another and now because the Highway Code says you 'should' (rule 115). But as this is only a 'should' not a 'must' and because rule 114 says we 'must not' use lights in any way which would 'dazzle or cause discomfort' to any road users then clearly even the Highway code makes the negative aspects of dipped beam a priority too.
It turns out that we are not required by law or the Highway Code to run around well lit built up 30 MPH areas with our head lights on at all!! It is totally discretionary.
Let's then be an advanced driver and reason this through:
Any medical practitioner and optician will confirm that to shine bright lights at each other, reduces the ability to see each other and anything in the surrounding vicinity. This reduces the information to the brain and to which we respond accordingly. In driving of course this is crucial. Drivers need as much information as possible and as quickly as possible to make vital driving decisions. They will also confirm that the iris of the eye contracts rapidly to reduce the light entering the eye but the recovery to normal can take several seconds and thus prolonging the lack of information to the driver's brain.
So, as you would think, shining unnecessary bright lights at drivers then is not a good idea at all.
What does it achieve ?:
All these lights achieve is a focus on a massive source of light and very little else. Any advantage to the user is lost totally by equally bright lights coming the other way!
What does it cause ?:
Many night-time urban accidents.
Well taking the medical fact to a conclusion then this must be so.
But now let's look at a typical urban 30MPH and study these images.
A well lit urban street with a car approaching. We do not see the car or anything after it, just bright lights. By now your eyes would already be closing down your vision. Unlike our camera lens, even the foreground would be blackened too.
Now imagine a wet road, the added glare from it, rain on the windscreen, or on a motorcycle visor, the increased stopping distance in the wet when information to the brain is even more crucial.
Here is the same road, but now with just tail lights, we can see the car and much further on too but in this case your eyes are fully dilated and taking much more in.
This next shot is a better idea of the lights pointing directly at a driver but the camera does not capture the true 'blinding effect' and long eye recovery time.
And below here too.
' There is no evidence that drivers blinding one another unnecessarily in well lit streets, especially in the wet, causes accidents, kills and maims because our stats don't say so. So we will continue to ignore obvious causes of night-time accidents and continue to prosecute perfectly safe drivers who are not about to cause an accident instead. So there!'.
Well that is the gist of their answers to me on this. Of course there are no stats simply because, over the last 40 years since this lunacy started, no stats have been kept have they? But stats should never be used when the answer is self evident and obvious in a life and death issue should they?
Here, the thinking driver on side lights only. See how much more you can see of the car, the road and other surrounding detail.
The following video was taken on a fine night but with rain water reflection, rain and smeary windscreens it's ten times worse. No stats are kept on how many this has killed over the years.
Please note that the road is as bright as it appears as the street lamps pass the camera. This proves the darkening effect of bright lights. But street lamps are not in the eye line or as bright as car headlamps.
ARE YOU A HEADLIGHT LEMMING? Do you think it makes sense to point bright lights at one another unnecessarily?
See this supportive article Vision