It is clear that some stories are boosted up, and some are boosted down, and it is not clear the process those get chosen.
It may be that "you find them interesting is enough", and it's your site so this is not a complaint, but it is not a transparent process because despite "thousands of comments" there is little documentation or explained policies.
We know there's an "anti flame war" trigger on the down side, but of more interest is what causes stories to jump hundreds of spots and that has never been well explained to my knowledge. (Or perhaps it has but I haven't been to read such an explanation).
Trying to write comprehensive policies would end up interesting only the sorts of users who like policies, including the sort who will raise objections no matter what we do. The more policy we produce, the more objections and meta concerns they will raise, so to go down that road would be to perform a DoS attack on ourselves. It would suck limited resources away from things we can do to improve HN for the community as a whole, instead of just a vocal, litigious few. Since we're going to get criticized from this angle no matter what we do, we may as well take our lumps up front. If that sounds harsh, I'm sorry—it's mostly because policy-writing is the last thing my soul cares to do, and the bureaucratic parts of this job make me grumpy.
HN has always been curated, and that involves human judgment and interpretation—there's no way around that, no way to spell it out, and certainly no way to formalize it. As far as I can tell, the community is somewhere between fine-with-that and prefers-it-that-way. HN has always been a spirit-of-the-law, not a letter-of-the-law place, and we want it to stay so.
But we're fully open to answering questions. I spend hours each day doing that, in threads and by email. There's basically nothing people ask about HN that we don't answer. Before someone objects to "basically", I'm throwing that in because there are always corner cases (e.g., a question we can't answer because it would compromise some other user). You can't run a site this complicated without inconsistency. But the principles we practice are deeply about openness and satisfying curiosity. Even though we don't publish a full moderation log.
As for stories "jumping hundreds of spots", if you mean jumping up, that's the second-chance pool (described at https://news.ycombinator.com/item?id=11662380). If you mean jumping down, it's some combination of software penalties and/or user flags and/or moderation downweights. Most often it's user flags.
It may be a matter of perspective because from my point of view, the comment you have linked is the past to which I was referring: that is from 4 years ago.
That may have flown by for you but is much of the time I have been visiting HN.
My guess is that flags are responsible for a lot of weird movement in the front page ranking. You flag an article and it starts losing spots - a number of people do it and the article can die entirely. The flag count is hidden to prevent bandwagoning but is an important signal. Thus front page posts move in mysterious ways as if guided by an unseen hand.
Well they are and the hand is users flagging posts. Plenty of times I've seen
Where A is ranked above B despite being older and having fewer votes (the signals we can see). I think the missing link is flags. I bet if we knew the flag count the front page ranking would make more sense.
It may be that "you find them interesting is enough", and it's your site so this is not a complaint, but it is not a transparent process because despite "thousands of comments" there is little documentation or explained policies.
We know there's an "anti flame war" trigger on the down side, but of more interest is what causes stories to jump hundreds of spots and that has never been well explained to my knowledge. (Or perhaps it has but I haven't been to read such an explanation).