Posting a blog post to HN or any other site is neither a marketing strategy nor growth hacking.
If you discovered that getting a blog post onto the HN front page leads to xxx new users, maybe that is worth it.
Now work out how you can get enough votes to get that result. Lets say you find that asking a new or existing user to upvote a post on their 5th page view leads to 50% of them upvoting.
Now you can easily work out a ROI on creating a piece of content, you have some code in place to help your audience get the result and it generates xxx new users each time.
If you discovered that getting a blog post onto the HN front page leads to xxx new users, maybe that is worth it.
Now work out how you can get enough votes to get that result. Lets say you find that asking a new or existing user to upvote a post on their 5th page view leads to 50% of them upvoting.
Now you can easily work out a ROI on creating a piece of content, you have some code in place to help your audience get the result and it generates xxx new users each time.