So basically, whether you get up at 5AM or 9AM, 90 minutes later you’re great. But the 5AM folks are having test #2 at 3:30 in the afternoon when most people are having the mid-day slump, so they didn’t fare so well. The 9AM folks, on the other hand, don’t get test #2 until 7:30, so they test out better. Interesting.
I like the takeaway — work around your own energy levels. Makes sense to me. :)