Well, we kill everything the editors think is excessively lame. Downarrows would produce better results iff the userbase at large were better at deciding what was lame, which is probably not the case. Downvoting is often done reflexively, whereas killing something is a fairly momentous choice one thinks about first.
I think that HN does not really need down-voting for articles at all, but on the other hand, it needs some automated killing functionality.
EDIT: [About the editors, it takes an hour and sometimes more for a link to be killed, at least when I flag a link and I see it for hours - happened today. So maybe automation will help in any editors shortage]
For example, someone few days ago submitted your article "Why TV Lost", although it was already submitted, and we already discussed it! But he was able to do it, obviously because the submission detection script does not think that "www.domain.com" is the same as "domain.com", and treats them as different links.
Also if a link is submitted previously and it was dead because it's spam, then if a user tries to resubmits it again it should be killed automatically. Like Google homepage, myspace and all of these bla bla bla.
There are zillion techniques for preventing spam, and you know it better than me for sure.
But there is a vision that you have about spam on this website, that I don't really understand yet.
But google.com is the same as www.google.com? and ycombinator.com is the same as www.ycombinator.com? Got what I mean!
I am talking about the "www" which is the acronym of "world wide web", and it's automatically assigned to any domain name, so usually domain.com and www.domain.com points to the same host, unles if the sysadmin changes it which rarely happens.
I am talking about the "www." and NOT any other subdomain that the sysadmin/webmaster can add/change or remove.
I am sorry if you misunderstand what I am talking about.
Oh really?
I am sorry because I did not know it before.
Thanks for informing me, I really appreciate it. I am so glad that I am learning something new here everyday.
Thank you so much for your explanation, I really appreciate it.