What time will X occur on a particular future date? E.g. meetings.
What time will X occur in another time zone?
What time will X occur across multiple time zones that shift at different times?
What time will X occur across multiple time zones where one doesn't shift at all? E.g. meetings with people in Arizona.
How long ago did X occur, across a transition? E.g. correlating Unix time to civil time.
How long is X, where X is an event spanning multiple time zones that shift independently? E.g. plane flights.
Does my cron job need to run intermittently every X hours, or at 24/X particular times every day, or every X hours but managed so that processing doesn't intrude into normal business hours?
Personally, when I'm in the wilderness my circadian rhythm follows the sun. Up at sunrise and asleep not long after sunset. That's not how I work when I'm living in society, so I don't see why animal adaptations are particularly relevant here.
On a social level, the shift causes tremendous levels of stress to people. It essentially creates a day of national jet lag, for no real benefit that I can see.
None of those are difficult in the modern world. Computers have pretty much solved all of them. There are confusing to talk about cases. But none that are truly problematic.
Consider some of the most sensitive for people. Take your medication twice a day. What do people do when they fly across the country? Most don't keep the same schedule they had back home on the medication. They just start doing it at the new place.
Folks that do have "take this exactly every 12 hours" rely on a timer, not a clock.
Even talking about how long ago something was is just not that important for folks in most scenarios. Consider, when people move they don't change their birth date if it would have been a different day in the new location. (That is, nobody does their birthday by GMT.)
Now, about the only idea I fully reject is that we could just tell all businesses to change their opening hours so that we don't have to change the clocks. This is mind numbingly crazy to me. The entire point of changing the clocks is to get everyone to update together.
When a meeting is set up and time shifts happen, in practice people don't know what time the meeting is. Same for the rest. I'm not concerned about whether you can calculate it in theory (you actually can't in general, just the common cases) since it doesn't happen reliably in my experience. There were also many cases of things incorrectly applying DST when I lived in AZ.
Also, I assure you people care very much about how long ago they worked when it involves their paychecks and hours worked. Datetime/DST bugs in payment systems and other critical computers are scarily common.
Plus the billions in social costs. Children have to dream with sleep deprivation, hospitals have to treat more strokes, pollution worsens, and criminals get longer sentences.
I'm not sure why changing opening hours is difficult. It's incredibly common to have off-season and high season hours in tourist towns. You don't have to coordinate anything. If the idea of multiple hours is too difficult for anyone, they can simply pick one or the other. Nothing bad will happen.
The benefits we get for the trouble of changing the clocks are minor.
If you are saying that mistakes will be made, I agree. People make mistakes all of the time. About things easier than schedules.
If you want to single out the idea of "shifting timezones" being how we accomplish DST. I agree that is problematic, at best. I can assume there were reasons to do it by completely changing what timezone an area is in. I struggle to understand them, myself. Especially when we don't do the same for other time shifts. (Leap years and seconds, in particular.)
I further agree that doing it in one hour jump is bad. Is literally why I suggest shortening the jump to 10 minutes would be fine. Argument being that that is far more natural for how time was felt by people for most of history. (Indeed, originally, hours were not fixed in terms of how many minutes they took.)
But no, nobody cares what time you said they clocked in yesterday. They care that you accurately pay them for how long they were clocked in for. Obviously, you have to make any system that deals with those work correctly. But, again, people make mistakes on those already, irrespective of timezone changes.
For evidence, see how little energy people expend on how incomprehensible airline tickets are. Look at a ticket and see if you can quickly say how long a flight is. It isn't like they don't know. It just doesn't matter on your ticket. (Even if I like to consider my options based on how long I'll be in the air...)
Is it a good argument to not necessarily change things? Yeah, which is why I think my suggestion of 10 minute changes is largely silly. A lot of inertia in the system we have is not necessarily a bad thing.
Getting everyone to change their operating hours just feels daft to me. And, ultimately, how is that any different?
For example, you want to get it so that schools start/end an hour earlier starting a week. Which means that we still have to deal with the idea that you have to shift your sleep. Probably wise to also go to sleep an hour earlier. And, yeah, I think people could adjust to knowing that they have to change their bedtime from 9 to 8, for example. But, there is a reason we try to keep sunrise and sunset as close to consistent times as we can. No matter where we go.
I'm somewhat sympathetic to the data about how much worse the week of the hour loss is. I'd be curious to know if that is better or worse in recent years. And I genuinely don't know how to square the fact that the data dang near cancels out with how much better it is in the week we gain an hour. That, honestly, feels a bit too convenient. (And again, this just gets me back to the idea that the problem is losing a full hour.)
What time will X occur in another time zone?
What time will X occur across multiple time zones that shift at different times?
What time will X occur across multiple time zones where one doesn't shift at all? E.g. meetings with people in Arizona.
How long ago did X occur, across a transition? E.g. correlating Unix time to civil time.
How long is X, where X is an event spanning multiple time zones that shift independently? E.g. plane flights.
Does my cron job need to run intermittently every X hours, or at 24/X particular times every day, or every X hours but managed so that processing doesn't intrude into normal business hours?
Personally, when I'm in the wilderness my circadian rhythm follows the sun. Up at sunrise and asleep not long after sunset. That's not how I work when I'm living in society, so I don't see why animal adaptations are particularly relevant here.
On a social level, the shift causes tremendous levels of stress to people. It essentially creates a day of national jet lag, for no real benefit that I can see.