Not sure if anyone was interested in this still, but last night i just found out this feature works even in a completely dark room. I had my phone plugged in on my side table next to my bed last night and had turned the lights off so it was a pitch black room, saw the red status light and swiped my hand over the phone and it was able to wake up and show the "at a glance" thing with the time and blue glow. That makes it so useful!!!
I even woke up in the middle of the night wanted to see the time, so i waved my hand over it (still pitch black) and was able to see the time then went back to sleep! Such a great feature.