Kind of related, but there is a concept of polyphasic sleep - where you sleep for small increments throughout the day (like 30 minutes every 3 hours). I did it for a bit at a startup thinking we were "hacking sleep" and "getting more productive hours out of every day!" - It takes awhile to transition to it, but once there, your scheduled "sleeps" are insane, 15 minutes, feel like straight to REM. The main problem was if you missed on schedule sleep you were a zombie.
Yeah, when I was looking into the plausibility and function of polyphasic sleep, I stumbled across studies from the US Airforce. Their conclusion was similar: In a controlled enviroment, it can be spectacular and work really, really well.
However, it is very, very fragile to any kind of interruption, so they stopped looking into it.
When I worked an overnight shift and lived alone, I got into a pattern of 2 to 3 hours a go three times a day. These were after work, halfway or so through my personal time, and before work. I used these separate times in between sleeps for work, almost exclusively for chores, and a dedicated slot for hobbies. I started each one refreshed, which was great. It doesn’t necessarily work so well when aligning your life with a partner.