I'm still frustrated that WikiLeaks sent out a call for programming help months ago, lots of HN folks emailed offering to volunteer, and nobody even received an email reply:
Sadly, the link was just to the main page and none of the several ways I tried (mediawiki's history, api, Special:Export, archive.org, or any of the wikileaks mirrors I tried) allowed me to figure out what their request actually was.
That junk is automatically generated, and is frequently not noticed. It seems like it causes a large number of dupes both here and on reddit, but I think it's almost always an error. It's easy to forget or not realize that it will result in a repost because the system doesn't check for that. The trick of adding ?repost, etc is sometimes used to make a repost on reddit, but I don't think I've seen it here.
Also, I wouldn't argue that all reposts are bad. If it received 0 comments and votes, despite being an interesting article, perhaps a single, better timed repost is in order. I wouldn't suggest resubmitting it repeatedly, but I don't think that single resubmissions are more harmful for HN than good content being missed.
It's the OCD in me - I just get annoyed that duplicates keep getting posted without people checking. I know I'm in a minority, I know most people don't care, and I know some articles deserve a repost because they really were valuable, even if no one saw it first time round.
But I'll keep marking duplicates so people are at least aware that the item isn't new, and so that, with any luck, discussion doesn't get split unnecessarily.
I find this interesting considering Wikileaks was so quick to comment via their Twitter feed.
http://twitter.com/wikileaks