I have an idea: it might be interesting to have a "pinned articles" section at the top of HN, similar to announcement threads in forums. It would only display for logged-in users (so it wouldn't bother anyone who was just anonymously browsing the site) and, once you were logged-in, you could simply close the div displaying them. The prime candidate for a pinned article would be the HN guidelines; this would probably be another.

Closing the div would actually just mark all the pinned items currently in it as done-with for you, so any newly pinned items would still appear. If you closed the div when you didn't mean to, you could also check the new "pinned" section on the top banner, which would display all pinned links regardless of done-with status.