> The whole presumption that you want to spend 8 hours in an ergonomically ideal position without motion seems like bunk.
That’s because it is bunk. Low back pain researchers found ages ago that the most ergonomic setup for alleviating back pain was the one that let you shift positions every 15 minutes or so. There is no position so ergonomic that the body can tolerate holding it for extended periods of time.
Sorry - are you asking the parent for a citation on how it made them feel?
That's actually a perfectly legitimate thing to ask for. Our feelings and subjective experiences are very real, but our recall of them is terrible. Properly tracked, they're useful data, and such tracking could be cited here. Summoned up from memory, they're noise.
I don't want to live in a world where feelings are only valid when backed up with a spreadsheet.
Parent never described how it made them feel -- they described the motions they made, and called that not ergonomically safe. If op has said "I got a kink in my neck," it'd be a different story.
The whole presumption that you want to spend 8 hours in an ergonomically ideal position without motion seems like bunk. Indeed, I find changing positions to be much more ergonomically valuable than having an ideal position. If I spend 30 minutes each across 16 awkward positions, I do just fine. An ergonomic chair, mechanical keyboard, perfect-height monitor, etc. for an 8 hour stretch each day hits me much harder.