This actually does NOT work for me. I try it sometimes in the weekend, I sleep as long as my body "tells me", but then I get up at 9am and feel totally tired. I

This actually does NOT work for me. I try it sometimes in the weekend, I sleep as long as my body "tells me", but then I get up at 9am and feel totally tired. I feel much better when I set my alarm clock to get up early.