I'll admit it. On any thread I read I scroll down to the bottom and generally upvote the lowest top-level comment. Often if very snarky, there is good truth to what's being expressed. I rarely upvote the most upvoted top-level comment as I find them often to be puppeting along some type of information in a grade-grubbing type of way. I went to med school I know that type.
I think voting is hugely important to HN's fate yet its basically forbidden to mention it. Yet, there are all these rules on what constitutes a good HN comment. Weird if you ask me.
What's your approach to HN voting?
Downvote: Anything negative for no real reason. Reddit-style punmanship.
I recursively apply this strategy for all comments.
Downvote = notably below-average contribution to discussion, please don't do this (even if I agree with the point being made, e.g., do the way it is made, or to it being made when it is off-topic deflection from the thread topic.)
Downvote: I rarely down-vote. I know it is ok to down-vote to show disagreement, but don't use it that way. I down-vote hateful comments.
Downvoting: I can't yet ;-) If I could, I would do it for comments that are way off-topic, contravene the guidelines or are gratuitously negative (especially if they involve personal attacks on other people in the discussion).
One thing I cannot stand is downvoting because you simply disagree with an opinion. We need diversity of opinion here, and on more important subjects than whether JS or Ruby is better for web dev. (As it is, the HN community is already pretty strict about enforcing a certain mindset on commenters. That is a Good Thing where values such as "Be polite" and "Be constructive" are involved, but can quickly become very dangerous if we start codifying opinions.) Basically, downvoting because of opinion pampers to confirmation bias and should thus be avoided. Note that I consider upvoting for opinion fine, as the psychological effect of an upvote is significantly weaker than that of a downvote - at least in my experience.
I'm disappointed guys...