I have it. What I've learned from my doc (a researcher in the field):

It's primarily a specific genetic mutation that affects many of they body's cyclic timers, but relevant here is that the circadian feedback loop is no longer able to lock to a 24 hour day/night cycle at all. The timer technically works. You're perfectly sensitive to light/dark, but you're hitting a PLL with inputs faster than its ability to make meaningful adjustments. That's not the case with DSPS.

Sleep apnea diagnosis is relevant here, it also breaks the breathing reflex timer. Imagine finding out at age 40 that you've not, in fact, slept more than a few minutes at a time your entire life, because you wake up just enough to take a breath every 3 minutes or so when a secondary suffocation reflex goes off.

This might be the scariest point. To me at least, it only felt obvious after stating it directly.

In all seriousness, every aspect of this comparison is somewhere between deeply flawed and invalid. No point dwelling on just one part.

[reads]

...Jesus H. F. Christ....

Every generation thinks they discover sex and audio analysis for the first time.

[And don't call me Shirley]

For example, oxygen saturation monitoring revealed my at-rest breathing reflex is completely broken due to a known genetic flaw. You know the memes about 'your breathing is now under conscious control'? Mine actually is.

That led to a sleep study-- and, yup, I don't breathe when I'm asleep. I wake every two or three minutes, all night, take a few breaths, and go back to sleep. And have all my life. The mystery of why I'm 'such a light sleeper' also revealed.

Doc I saw about it remarked the mutation is probably more widespread then we know because 'no one is looking for it'. It also completely freaked out a few anesthesiologists.

[There are other reflexes around breathing, and no, I can't just hold me breath as long as I want. The physiological reminders to breathe are pretty strong! But I routinely see my SP02 at rest drop below 70.]

It's the first 'desktop' I wanted to use, and have used for more than a few weeks, approximately 10 years now. I've generally liked the changes and improvements over time. It finally budged me off of (wait for it) vtwm.gamma.

To each his cup of tea.

But you're right-- it was too late to save the QL by then.

Of course, that wasn't the only problem with the machine, not by a longshot. I did my very first commercial hardware hacking in high school building/selling plug-in 'spiderboards' to protect the oh-so-fragile ZX8301 chips, and got my first oscilloscope in college to chase down all the ground bounce that was still occasionally killing the NMOS ROMs...