Its not a "habit", its hard-coded and there is strong evidence that forcing your sleep schedule to change has negative health consequences. Underlying all this is an insinuation that if you just eat better and exercised you'd wake up at a normal time. Night owls do get exercise and eat healthily. This advice never seems to be applied to early risers, it comes from a cultural perception of night owls as defective.
Maybe. I was a night owl for 30+ years, but then had the same experience as OC when my other habits changed my sleep cycle changed too without any of the grogginess and frustration I had before when I only tried to change my sleep pattern.
Bodies are different though so no doubt our experiences may be very different.
I'm happy it worked for you, but I consider us victims of a society that arbitrarily enforces waking hours. There's no reason a programmer can't work noon to 8 if that works better with their sleep schedule. Ditto for most other office jobs. Core hours are reasonable compromises.
On the one hand our lives will be easier if we just got with the program. But things will never get better if we acquiesce.
