Hello Virgil, Hello Alaric,
Glad you're both doing well -- and if you won't mind some avoided-accident detail in this completely unrelated (Z3 / DRL-1) thread, and on the off chance the account might someday help encourage others to heed the great advice given on this forum, here's what happened:
The Advice
I first came to this forum seeking help with my 2000 VW GTI's lighting, which (it turned out) I had thoroughly messed up while trying to "improve" it. As bulb replacement on that car is a pain (reaching the bulbs entails removing the front bumper), I had installed "Long Life" H7s that I kept running for many years, and when those bulbs dimmed to the point that I could see my car's own shadow in the light cast by cars following behind me, I tried to "correct" matters by re-aiming the headlamps via the infamous shine-the-lights-on-a-garage-door method. There were other issues as well, and the two of you proceeded to set me straight on many & varied fronts, but most notable was the advice to (1) replace the Long-Life H7 with Osram Rallye 65W; and to (2) get the headlamps properly aimed (which wound up shifting a lot of light up and away from the foreground and into the middle distance)....
The Avoided-Incident
In late November 2017 (after the GTI's lights were fully corrected), I was driving back up to Boston with my wife after a day/evening on Cape Cod. It was a moonless night of heavy dew, and New Englanders will readily appreciate how dark such a night can be (the road surfaces suck in the damp, and everything is pitch black). We were on a divided highway, where two lanes had momentarily broadened to three via an entrance/merge ramp, with a Prius merging in from the right about 30 yards behind us, and a faster-moving black sedan of some sort overtaking us on the left. As the sedan went by I dimmed my high-beams, and the sedan continued past, maintaining his low-beams...
When the sedan had pulled ahead some 50 yards or so, its tail-lights (which was all we could see amidst the blackness) suddenly did a funny little "cant" -- something subtle, between a pivot and a tilt. Simultaneous with that, little dancing particles (like clods of dust or grey-black snow) became visible in the distance, moving almost as fast as our car. The Prius behind us and to our right was trying to accelerate up to speed, so we sped up a little to maintain some separation, and eased into the right lane to get around the mysterious dancing "snow". As we did so, the sedan's brake lights came on, and then a dim dark shape -- a very long, low, complex-looking shape -- appeared before us, lazily pin-wheeling from left to right. As we passed this shape (by this time both we and the Prius were partly in the far-right breakdown lane, the Prius never once letting up on the throttle), it revealed itself (we realized in hindsight) to be the sedan's front bumper / front apron assembly, with the sedan itself (my wife reported afterwards -- she had turned to look out the back window) now receding in the blackness behind us, headlights off and surrounded by a faint shower of red-orange sparks.
What had Happened
As far as we can guess, the sedan had hit something very solid -- something the driver never saw, and which tore off the front of the car and sent fragments flying into our lane.
What I learned
Virgil and Alaric have been consistent in this forum about (1) the need for headlights to be properly aimed; and (2) the dangers of over-driving one's low-beams. Just seconds before this incident, I had had a fine view of an empty highway illuminated by my (now-excellent) high-beams -- but as the overtaking sedan went by, I had shifted to my low-beams. The subsequent incident then evolved so suddenly and so strangely that (to my shame) I never flicked my high-beams back on: if someone had described this scenario to me and asked "What would you do?", I'd have replied "I'd turn on my high-beams (of course)", which is something I regularly do when appropriate -- but on this dark Massachusetts highway in November 2017, I was so perplexed by what was (very faintly and dimly) happening in front of the car, and my thoughts were so occupied by what to do and how to do it (it would have been much easier if the Prius wasn't so dead-set on accelerating up to speed), that what I thought had become a "reflex" (flicking on the high-beams when there's something I can't see) turned out not to be a reflex at all.
So I was over-driving my low-beams -- and fortunately those low-beams were (thanks to this forum) very good low-beams, well-aimed, with very controlled foreground illumination, so that a suggestion of dim, dancing "snow" (pulverized bits of black plastic on black asphalt) could be seen far ahead, giving enough warning for us to move over before encountering more solid pieces of the wreckage.
Addendum
Friends have asked us if everyone was ok in the black sedan. We've no idea, save that the brake lights came on sometime after the presumed collision, so the driver at least was conscious and responding to the situation. As for why we didn't stop: we didn't know what had happened (and from the way he/she was driving, the Prius driver probably never saw a thing -- after following us into the breakdown lane, the Prius overtook us and shot off) -- it was so dark and dim, and what we could see was so nebulous, that we didn't even realize there had been an accident: it was only afterwards, when we heard the highway had been shut down shortly after our passage, and when my wife mentioned seeing the orange-red sparks, that we pieced together what must have happened.
Anyway, thank you again for the consistently great advice you two give on this forum, and hope you both have a great summer -- all the very best.
