Since popular HN submissions will often hug the site to death, a nice feature would be to automatically check the top 3 caches (archive.org, Coral, Google) imme

Since popular HN submissions will often hug the site to death, a nice feature would be to automatically check the top 3 caches (archive.org, Coral, Google) immediately on submission, before the page goes live on HN. If the cache doesn't 404, the content could be quickly parsed to check it matches the submission and, if so, automatically include the cache link at the top of the submission page. This would save people manually posting these all the time and would, in many cases prevent the case where it becomes impossible to retrieve a cache, because nobody thought to access one before the slashdot effect occurs. Or, as in this case it seems, the article is pulled. It would also be nice if, 24-48 hours after submission, the only cache link remaining is archive.org (if they have the page), so the content is retained permanently as-submitted. It's rare, but sometimes a page will be updated so the comments no longer make sense. It would also be nice to include a link history in the same area (have requested this before), in case the original submission is changed by the mod. Usually when this happens the notice is the top comment, but sometimes it isn't and the discussion can be quite confusing as a result.