sctb is a moderator (kind of annoying that you have to google that) [1] and given their statement it indicates that "soliciting upvotes and booster comments" is disallowed/discouraged. Yet, that information is not part of the official HN guidelines [2] but is merely mentioned in the HN FAQ [3]. My point being, if telling your users about the HN post you created is disallowed, then why is it not part of the guidelines and merely hidden among the FAQ? Like I said, guidelines are to be read and followed, but I wouldn't expect from people to read the FAQ to find all the 'rules'.
[1] https://news.ycombinator.com/item?id=12073675