I wonder if the study corrects for students that just stay up late for parties, etc., and just strip themselves of sleep when it could be avoided. It's quite ea

I wonder if the study corrects for students that just stay up late for parties, etc., and just strip themselves of sleep when it could be avoided. It's quite easy to move your bioclock forward bit by bit, esp.for social reasons. It is very hard to roll it back (some studies suggest it's better to just roll it forward more and more instead)