Can't say I haven't been told that one before With DSPS, your entire biorhythm gets bumped off course and stays that way, this being the main difference between DSPS and a messed-up sleep schedule that can be remedied within a few days to a week of easing back into a more socially-acceptable pattern.

A thing I've noticed with my DSPS is, although there are times when I can (barely) maintain a "wake-up-in-the-morning" pattern - with great effort - it will always, always snap back to what I'm most comfortable with.

I've always felt best and worked best when I went to sleep at the crack of dawn (in summer) or close to it (in winter). My most productive working hours are 10PM - 2-3 AM. It's been like this for years. When I was a kid, I used to wake up a few hours after bedtime and read until morning because that's when my energy was at full. That hasn't changed since. I'm sure other people can relate.