In reply to andy:
> I have a Hope District+ on the back which is visible from space, so you're not missing me.
How large is that light? A bright but small light can be quite difficult to interpret if there are no other visual cues. Think Father Ted: is it a dim light close to, or a bright light far away? Wearing hi-vis (as GrahamD says, it's not just retro-reflective) as well provides two quite different visual references for the same object which makes it easier to interpret what you're seeing. I think that's better than just two lights, since an observer still doesn't know how far apart the lights might be mounted on the bike (ever had a car coming towards you at night that turned out to be a motorcycle with twin headlights much closer than you thought?)
Driving around Edinburgh in the current dank, gloomly evenings it's astonishing how both cyclists and pedestrians, when wearing dark clothing, can merge into the general murk even on ostensibly well-lit urban streets. (I remember a few years ago when we offered to take my 90+ year old Dad shopping to get him something more stylish than his usual beige jacket, he declined on the grounds that the light-coloured jacket meant he was more likely to be seen at night. On reflection I reckon he had a point.)
Based on how difficult I know it is for drivers to see cyclists at this time of year, my conspicuity kit consists of the following:
- a BS-compliant LED rear light/reflector combo permanently fitted to the rear offside seat stay (I find it depressing how many bikes I see that don't even have a reflector, let alone lights);
- a bright CatEye multi-facet red LED light on the seat pin. This has two separate light circuits, each of which can be switched between off, steady, regular strobe, left-to-right-to-left cycling and random strobe. That's good for getting attention;
- hi-vis armbands with flashing red LEDs built in;
- a red LED on the back of my helmet;
- a cycling rucksack in hi-vis material with reflective detailing;
- a CatEye white front reflector with a yellow LED steady/flashing position light built-in;
- a Fluxient 1600 lumen LED headlight with three power settings+strobe;
- a backup LED torch which can be bungeed to the handlebars if the big light fails.
Which of those I use depends on the prevailing light conditions but I tend to agree with TC that it's safer to err on the side of caution and not just wait until official lighting-up time before some of the lights go on.
Of course we would all be a lot safer still of some people didn't have a tendency to hoon around with little regard for their own safety or that of others - but you do what you can and, as TC says, it's hard to mitigate against idiots.