but why is he being down voted? All he did was to point out that this article has been published before.
Maybe there are some interesting comments in the "dupe" thread? (in this case no, but you get the point)
I'm still new to HN and I find the up/down vote behaviour rather peculiar from time to time. This is such a time.
Providing a bit more context in your post would have probably helped.
If there was discussion on the original submission it would have been useful)
Clearly, due to getting enough karma to put it on the front page this time, my comment is indeed now irrelevant. The post was clearly just missed the first time as you say. Whether this is a problem with the karma/new post system or not is a different matter - and probably not one for discussion here.
I didn't think I'd get downvoted though, given when my comment was made, but your points are fair.