If the vehicle in front has an autodimming mirror, it will take time to react. When you turn your lights off, the mirror will un-dim - then when you turn them on again you'll distract the driver as it will take time for the mirror to react and dim to the brighter lights. Given you'll be turning them on about the time the driver moves off, isn't there also the risk they think you're flashing them out of impatience? .[/quote]
Oh dear, oh dear oh dear! So, if as a non IAM driver, you drive right up to the vehicle in front, your lights are then obscured by the boot/tailgate in front and won't cause the autodimmer to operate. Then, when the car in front moves off, your lights will then cause the autodimmer to operate. Similar situation? This is the norm as I have observed it.
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Also, AIUI if your vehicle has Xenon (gas discharge) headlamps, frequent cycling of them isn't good for their long term life.
It doesn't thank goodness - I abhor them. I can see no reason for such intense lights when the range to the illuminated target is a few car lengths ahead (at best). Because of their peculiar beam pattern they often seem to be flashing when passing over minor irregularities in the road surface.
There is an active campaign to declare them illegal and I have subscribed to it. The response from the DOT (I think) was that "adequate legislation exists to cope with dazzle".
It doesn't.
Now, there's an excuse for the first thread drift.