Yep, this. During summer internships in college I easily transitioned to a fully-functioning 11PM-7AM sleep schedule, but university's manifold distractions pu

Yep, this. During summer internships in college I easily transitioned to a fully-functioning 11PM-7AM sleep schedule, but university's manifold distractions pushed me to a 2AM-10AM schedule. And in high school I was chronically exhausted because I'd stay up playing Counter Strike until 12AM every night (in retrospect this probably also limited my achievement in XC and track...). Of course this is all anecdotal.