Looks like he learns, pretty much the same way I do. It seems to be common.
One of the nice things about being retired, is that I don’t have to retire. I just direct my own work, instead of having knuckleheads trying to steer the boat. Since I like learning, I look to do stuff I don’t already know how to do[0].
I don’t think he’s retired, but he seems to be in a place, where he’s free to follow his own muse.
[0] https://littlegreenviper.com/miscellany/thats-not-what-ships...