Ahhaa, this reminds me of my school days. Between me and my sister, she would study whole night and sleep towards morning and my habit was to wake up at 04:00 A.M. and study for 3 hours and not to brag I always secured more then her and she would get snappy at me during result time..hehehe
Yes I too believe that the grasping is much better studying and reading in that hour.