Oh sorry, I skipped a step - I was referring to the emerging trend of people adding an archive link as the first comment on HN for many stories, which this is going to accelerate.
Those comments are pinned to the top by the forum with replies disabled. It appears to be a manual process, not automated by user, link, etc based on the comments being pinned.
Indeed, and this is what I would like to hide as it's a distraction for me. I think it would be smarter to put a link in the header instead of messing up the comments.