For me, it was so enlightening (heh heh) about the natural light patterns of the seasons, and how they affected my health. While we have winter, it's not a cloudy winter. We have lots of sunshiny days with bright Alpine sun, low temps but no wind. On such days you go out with sunglasses and the parka open.

But as the days got shorter, I went to bed earlier this year. I shifted my ME time to early morning instead of late at night. And my sleep improved again.

Which it needs. At my worst I was getting 2-4 hours a night. It doesn't take too long for that to kill you.

I now take it with the utmost seriousness.