Let me explain. Currently everything has one score. So, give it a second score that also starts at 0. Instead of score "1 point" it would score "1 point (1 point at adult table)."
Then the adults at the adult table would immediately downvote anything that isn't adult (this only concerns its score at the adult table) and can upvote highly reasoned but nuanced posts, and so forth. However, there are not so many at the latter table. So, the former table might go from -2 to +100 maybe the second score has most comments untouched (at 1), with a few downvoted, and a few upvoted.
This way, you could have a children's table (current reddit) with its thousahds of votes, and good comments languishing at 0, and the adult table, where the same 0 normal score comments can have high votes at the adult table, and so forth.
So, here on hackernews, you could have a "serious" or a "founder's" table. And you could have a snarky table for people that just like having everything picked apart - where, "correctly" (per policy) we (the serious table) would vote the snarky comments down.
So, to illustrate. Here is a snarky comment "Oh, I see. So it's like a coupon system where you insert yourself into a transaction and book the whole transaction as revenue, deducting the actual 'rest of the transaction' as cost. So even though you lose on every transaction, you make it up in volume! Hey, it worked for groupon, right? :)"
This starts at 0, 0 for the snarky and serious table respectively. The serious table immediately gives it a downvote, so it is now at 0, -1, and then another, 0, -2, and soon it's hidden here: 0, -3. Meanwhile the people shifting through the trash say, "hey, ZING!!" and promote it, it gets to 5, -3, then 10, -3 then - if this place degenerates into reddit, hundreds of points, -3 respectively.
The serious or adult table is not impacted. It's not even visible. Meanwhile the snarky guys can have their children's talk.
(here is the rest of my comment. I shifted the above to the top for more visibilty.)
like many others I had a "rude introduction" to hackernews, not from real connections in the startup world (which I have) but from low-quality forums. In my case I regret even the choice of username, and would change it if I could (maybe indicated to show that it's new). I wouldn't now shirk away from using my real name or a close alias - something I never do online.
So, in my case what would have mitigated my behavior is seeing where my traffic was coming from and treating accordingly. I certainly wasn't typing it into the browser URL bar. Secondly, you could have a prominent button "New to hackernews? Learn about this community, which is a more serious one than most online communities: a lot of personal connection is on the line". Then explain why, and what we get out of behaving the way we do.
Finally, as of now I can either upvote or downvote a nasty comment. There is no right answer. But you can change this in a minute. If defining the correct way to vote as "downvote any negative comment not leavened by positivity - we need all the positive thinking we can get", then I would start voting correctly. It's like Wikipedia. I don't add what I know - I add what I can prove with a reference. I don't delete uncited folklore because it's not a good read - I do so because that's the correct action.
So, policies (as is the case with Wikipedia) help immensely.
It is too bad that more than a couple voting toggles would be too cumbersome; otherwise both ideas could co-exist as four sets of up and down arrows.