Question: now that the Google workaround no longer works for WSJ links, are they even allowed on HN? @dang has implied that paywalled articles without workarounds aren't allowed.
I mod a large sub-reddit, and I added an automoderator rule that basically tells people to paste the text of the article into the comments or the link is taken down after 2 hours. It is very effective.
There is no fair use for the copying of a whole text, and whilst the person who posts it is the one who has infringed copyright I am not so sure that you could consider yourself to not be involved.