> For example, if I tell my kids they can stay out later than 10pm any night if I know about it, then even if they message me saying they'll be out late tonight, actually staying out late is blocked by my ack.
Do you have an integration test for that in CI? That protocol sounds like the kind of thing which can break easily.
If I as a kid would hear that instruction "can stay out later than 10pm any night if parent knows about it" I would assume notification is necessary, but I would not return home early just because my parent did not ack it. And if my parents complained about that I would find them unreasonable.
Of course with your kids you might have been much more explicit about what you expect from them. Or who knows, maybe you are much more predictable in your response times than my parents were, so your kids might worry about you and call you if you don't respond anything.
I was just trying to come up with a scenario involving an obligatory ack (but not one in response to someone literally requesting a response every time), as a way of showing that while an ack is not typically obligatory, theoretically there could be a counter examples in the form of the ack-seeker twiddling their thumbs until ack, so to speak. I think you're right that these hypothetical kids would find it infuriating, and such protocol would work better if every ack-seeking message actually had a question ("11pm, ok?") making it explicit. It's just weird to pose a question if the answer is the same 100% of the time, and the only variable is timely receipt. How about this: "11pm, lmk" -- but the suffix is wasted keystrokes whatever it is.
It's rarely obligatory (unless the sender literally requests an ack) but is more to offer a data point just in case it happens to be useful. In some cases it will definitely be useful, like to unblock something that can't proceed until the sender knows you've been briefed. For example, if I tell my kids they can stay out later than 10pm any night if I know about it, then even if they message me saying they'll be out late tonight, actually staying out late is blocked by my ack. Of course, this could just be turned into a yes/no question awaiting my answer, but that would be silly considering that I only say yes; they're not soliciting a decision from me, just acknowledgement.