First, I'm extremely appreciative of Hacker News, its moderators, and the forum it provides for poor builders like myself to get some eyeballs on our infant products at no cost via Show HN.
However, it seems the 40-comment penalty is being applied to Show HN posts, which seems counter-productive to me. Isn't the whole point of Show HN to generate healthy discussion and answer user questions? Shouldn't they be exempt?
(Yesterday I posted a Show HN that had reached #15 on the front page when the 40th comment came in. Ding! Welcome to page 3. Irony: Several comments were my own, replying to questions.)
Source: http://www.righto.com/2013/11/how-hacker-news-ranking-really-works.html