Something went wrong because this was posted a day ago https://news.ycombinator.com/item?id=11347144
But I'm glad this has got its due notice at last.
> Are reposts ok?
> If a story has had significant attention in the last year or so, we kill reposts as duplicates. If not, a small number of reposts is ok.
In other threads, the mods explained that the dupe detector is weaker than expected on purpose so good stories get a second (and third, ...) chance to get popular. Sometimes the first submission don't get attention by bad luck (wrong time, another submission was too popular, random, ...). So it's common to see that the second or third resubmission gets to the front page.
BTW, Gus, at least some of the time I've been trying to use your preferred "Previous" format with points, days, and comment count when it seem relevant and useful (i.e. when it won't be killed as a dupe). You suggested it in a comment a few days or weeks ago. It's more work, but I'd bet it's more helpful, especially for new users. Most of the time, adding dupe links is simple and should happen quickly since it prevents split discussions and manual merges.