[IshKebab]

I don't really follow you to be honest.

> Not only are you trying to keep idle time low

Yes... I'm paid to work.

> you're trying to estimate essentially unknown timeline

Yes. The exact amount of time the task will take is unknown. That doesn't mean I have no idea how long it will take. The point of the estimate is to tell other people my idea of how long it will take. Even if I only have a rough idea it is probably a better idea than a lot of people.

Incidentally I've found that a lot of people don't understand that, and I have a hack! If you find yourself in a situation where you're waiting for something... let's say roadworks, and you say "any idea how long it will take?" and they refuse to give an estimate, even though they clearly have a better idea than you... What you can do is suggest an outlandish number, and then they'll say "oh no no not that long. More like x".

Worked every time I've tried it.

I can't parse your second paragraph at all.