Hmm, I still don't know if I should be surprised or not, as I'm having trouble parsing your last sentence. When you go to bed late, do you not set your alarm clock? Or do you sleep through your alarm? Or do you wake up naturally (but groggy) right before the alarm goes off?
I have attempted:
A) Going to bed late and setting the alarm at the usual early time
B) Going to bed late and setting the alarm a couple of hours later
C) Going to bed late and not setting an alarm at all
With A, I'll wake to the clock but be groggy. With B I'm not necessarily so groggy but still not as energetic as I would have if I'd gone to bed early and woken up early. With C I'll wake up naturally at some late time and feel pretty lethargic.
I was about to say that there are two dimensions here - groggy/neutral/awake and energetic/neutral/lethargic. Very r...
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