I know you said before you don't like the idea of stickies and anything 'important' would be better suited for the front page, but what if there is no front page? A board for a small group or group without [need for] a webpage, but still having a way to put up important info in the convenient form of a board post would be nice.
Seems to me stickied threads would be even more disruptive on a message board like this than on an image board. You'd have to keep scrolling past the stickied thread to read the actual discussion. It would totally dominate everybody's attention.
Better to put notices in include/mid.html.
Plus there's the occasional DQN in passing who glances at the top thread, sees it hasn't changed, and assumes nothing new has been posted to the board. And then complains loudly about it.
I like to think of the ability to sticky threads as a sort of PermaAge function, counter to PermaSage. Yes, it is annoying to many, but it also has its uses. It'd be nice to include it as an optional feature for mods and admins to use.
P.S. sorry for thread necromancy
I haven't seen any indication it has any use that isn't better served by some other mechanism.
I'd much rather spend effort making some sort of more automated way to put announcements on the top of the page, for instance.