> Are you suggesting that the sun is irrelevant to whether someone is a morning person, and only the time on the clock matters?

That wasn't my original argument at all, but yes - I'll argue this too.

I'm always sleepy in the "mornings" and get my best work done after I've been awake a while. It probably has more to do with metabolic flux than daylight.

I've occasionally worked so hard on things that I've had my schedule "wrap around" the clock, yet I still get the most work done in the back half of my day.