I agree with much of this (and eagerly await the next few years). The difference between sleeping 6 hours uninterrupted and sleeping 6 hours with 2 interruptio

I agree with much of this (and eagerly await the next few years). The difference between sleeping 6 hours uninterrupted and sleeping 6 hours with 2 interruptions is so dramatic. The cumulative effect of sleep deprivation takes awhile to really hit - the first three months or so I thought I was "fine" and then it really started to compound. Mood was really the most negatively hit aspect of my life. It's fair to say my appreciation of sleep is perhaps more psychologically-induced than physiological. Happens often when something is taken for granted and then ripped from under your feet for some duration. :)