The tl;dr of the article is: provide value to the HN audience by highlighting articles of interest, possibly adding some extra commentary, and you'll get karma points. No gaming, no telling folks "vote for my post".
Kinda seems like the system is working!
From my perspective, I do post self-promotional links, but keep them to 5-10% of my posts (don't really keep track, that's more of a 'look at the last 30 posts and see if I have 2-3 self-posts'). Keep the self-promotional stuff quality, and you have to share other posts too. (I got a warning when I posted less than high-quality links and took it to heart. The mods are definitely watching.)
In fact, one of my joys is finding an interesting article from someone else and having it 'hit' on HN. It's such a gift to all the writers out there who are screaming into the void.
It doesn't always lead to something, but it sure is fun to have folks reach out and thank me for the HN spike. Plus the HN crowd gets exposed to the quality ideas.
As I said, the system is working.