i think the OP is referring to the day time flashing mode, which is brighter than the night time flashing mode, but I think it's use during nights. Has to be, daytime flashing mode for day time riding has no other effect than you get notice sooner, at least for me. I personally, point the light straight out to traffic, on daytime flashing during the day.

On a different but related topic, I have collected data on how much pressure is left on my air horn after riding same route, same time, with runing day flasher and no lights. Got data on 10 rides, 5 with light and 5 without. Is a 14 mile strech I do on Thursday's from home to a church men's group. This data I collected over the summer months and started 2 1/2 hours before sunset and finished 1 1/2 hour before sunset, making the day light most effective, IMO.

The average pressure left on the horn for day lights running was 75 psi. The average for no lights was 40. That's filling the bottle to 100 psi and using my discretion as to when the horn would be require to catch the attention of the driver with enough time to react to me, rather than me react to him. Most of the time the horn was effective and I was able to keep my stride.

Somebody smarter than me could figure the numbers, but clearly, the cygolite 700 day runing blinkers, used during day, has a measurable advantage over no day running lights (reason in the first place I collected the data on pressure). I know its not even close to a definite study, however, it's enough to convince me to run them all the time.

And I suppouse, it also translate to an advantage during nights and could be measure somehow!

Double O