Think of it as a group ride mode, and then it might make sense. Some people become irate when you use lights in a daylight group ride. Yeah I don't get it either, but I think it would be nice to have it as an option. Perhaps the Varia radar itself has the resolution to detect the following conditions:
1) Car behind - flash on
2) No car behind, no cyclist behind - flash on
3) No car behind, cyclist behind - flash off or low intensity
I don't think this is a good idea ta all.
The light should be flashing all the time ... cars can see the light long before the radar picks them up. Plus I want non-cars to see me.
I'm pretty sure the light does change it's blink pattern when a car is detected.
Good idea. Also add an always solid mode (even with car behind). Some groups don't like any flashing of rear lights, especially on night rides. Very distracting.