I love sleep. Even as a newborn I slept 9 hrs straight before my mom forced me to wake up so I would eat LOL and then of course dozed off and on thru the day. I doubt I suffered from clinical depression as a baby.
I do power nap more when I have to time - like I'm on vaca but live without it when it isn't convenient. Heck, a whole continent has siesta time - they can't be wrong!
If someone is sleeping way way way too much - I would think they possibly have a sleep disorder and should get it checked out (I have three of them, so an organic reason to sleep often - but the idiot docs of course jump right to 'despression' b/c then they dont have to think).