My plan for dealing with downvoting is just not to display points on comments any more. The hard part is that to make that work, I also have to come up with alternative ways for people to find the comments they're most interested in on big threads.
1) No comments on a post until its at least an hour old
2) More time to delete my comments. I made one just a few hours ago I'd like to delete because of its tone.
3) A "stop being a jerk" flag. It would only be shown to the commenter, anonymous, and have no impact on points.
4) Alternative to #3: same flag, still anonymous, but too many flags "mutes" the commenter for 1 day.
Ultimately, of course, its a culture problem. We all need to take personal responsibility for our behavior. Whether or not that can persist in a forum of size remains to be seen (I am optimistic that it can).
Doing this adds filtering metadata and an gives additional incentive to downvote comments that don't contribute - they're going to be more likely to use few tags or inappropriate ones. On the other hand, posts that use a lot of tags simultaneously and actually encompass all of them are probably detailed and well-considered.
Downsides: more work to post(not always a bad thing), more room for nasty rules lawyering("This is not Hacker News").
What do you mean by: 'more room for nasty rules lawyering("This is not Hacker News")'?
I like your idea; how would I choose between 'information' and 'related'- or 'opinion' and 'related'? Would 'factual' and 'insightful' be more useful as labels?
This could also encourage users to vote more as voting would (hopefully) improve the filtering.
I don't care much for the points on comments at all. Comments that float to the top regularly defend commonplaces, and while they certainly deserve a positive vote, there's not much to learn from those.
But interesting comments, that I gather new insights from, are often written by the same commenters (->commentators? my English is lacking). Thus, a system that would work well for me, would allow me to rate individuals, so that on the next thread it will show me my favourite commenters first.
(edit: wow, suddenly lots of replies in this thread - maybe I forgot to refresh. I believe jefffoster's idea of Bayesian filtering may be more powerful than mine)
edit: although in all likelihood, I wouldn't know groupthink if I saw it, being part of the group... :)
Not showing downvoted scores on comments would never cause a user to exclaim 'why aren't you upvoting me?'
Disconnecting a user's visible karma from the hidden negative points a user acquires from negative/poor comments would be important for this idea to work well.
I think this is the key. People come to HN because the quality of the discussion is high. With increasing community size comes dilution, but only of the average comment quality.
In fact, as the community becomes larger there are more, perhaps many more extraordinarily good comments, so long as the original contributors are all encouraged to continue participating. These great comments are really the key.
Consider the Netflix Prize. Entries were judged based on RMSE. This is not the right metric, though, because out of all of the thousands of movies in the dataset, only a few dozen would ever be recommended to a given user based on any conceivable algorithm. And the user only really cares whether the particular movie that they use the algorithm to select is good or disappointing.
Similarly, users come here to read the exceptional comments, and a community in which every comment deserved to get 3 karma points would soon find itself without users.
In this way, removing comment scores may be part of an effective solution, but it may not be the crucial component because it only indirectly changes the accessibility of excellent comments.
Instead, actively trying to make it easier for people to read what they consider exceptional is a goal worth pursuing.
In this way, downvoting stops being a privilege you get at karma X and starts being something that's not to be squandered. I believe (or maybe hope) that every person here internally wants hacker news to be a good community, and that change will make them cognizant of the fact that downvotes are for special occasions where discourse is uncivil and not for "puttin' noobs in their places"
If a user hits the down-vote then a comment box opens requiring a reason. I don't mind down votes, but I can't stand not knowing why. It's like a (bad) dog owner who comes home and beats the dog for pooping on the rug. Poor dog did that hours ago and thinks hes getting beat just because owner came home. No lesson learned and it fosters a poor relationship between the two and encourages "acting out."
Additionally, if "the reason" received n down-votes HN could automatically cancel the DV to the original comment.
FWIW, One method I often use to find interesting discussion here is to just go to the threads?id= page for certain people who I think make interesting comments like you, tptacek, patio11 etc..
Then again, maybe I'm overly troll-paranoid.