Yes, this simple change could really work much better than all the fancy solutions. This is a social solution to a social problem.
I would suggest one additional thing, which is a little bit more invasive. After a user submits a comment, show a confirmation question like "Are you sure you are making a positive contribution to the conversation? [Yes] [No]"
I'm afraid that won't work for long. People will read it once and then comply. Maybe the second and third time they'll stop to think about it for a few seconds, but after that it'll get enshrined in muscle memory, without people actually reading the statement, let alone think about it.
I believe the posts are only part of the problem, though. The post obviously needs to exist, but it's the votes that make a comment insipid or insidious. Votes are multipliers: nobody cares about a stupid comment with few upvotes and a great comment with many upvotes is an even greater comment. It's when the votes are distributed the other way around that problems start.
Furthermore, a poster that gets downvoted will probably learn from the experience whereas if he gets upvoted, he's encouraged.
The problem and the solution therefore probably lie in the voting system. There's a few options I can think of right now:
* Giving high-karma individuals more voting power. Maybe tiered or maybe on an analogue scale. This has the problem that not all karma as it is now is deserved. (Take mine: I seem to get most upvotes for snide remarks and snarky questions, not for the posts where I want to make a point.) That said, karma probably still is an indicator of quality of posts, so it may work.
* Make upvoting cost a bit of karma. I don't think this will work well, since you'll end up with a closed economy where only the top X% of the users can really participate. And X will be decreasing when more players come in.
* Give a certain amount of points each day to spend on votes. (I'm not a user of that site, but I believe Slashdot uses it. Is that correct?) This will make upvotes a scarce resource, making people be more careful what they upvote. Of course, if unused points get deleted at the end of the day, people may try to spend unused points on things they wouldn't normally upvote.
* Up the current karma-limits. Right now you need X karma for feature Y, but with the influx of new users, karma has inflated somewhat. It's much easier to get to X if 10 people read your posts than it would be if only 1 person read it.
Just a few things of the top of my head. I'm not the smartest guy here, so it may not be a whole lot, though...
"I'm not the smartest guy here, so it may not be a whole lot, though..."
Please don't ever think that. 'Smartness' is just a function of few things which are in your control, at least in the long run. Thinking "I am not smart" is self-fulfilling.
High karma at the very least represents a stake in the site. Not every high-karma comment is worth anything, but virtually every high-karma user cares about the culture of HN.
True this. When I joined, I quickly found out that the people on the leaderboard tended to be the people whose names I remembered throughout threads.
I'd also place a bet that not too many people with lots of karma are flippant spammers; even the ones I think can be jerks sometimes (myself totally included) at least are putting in an effort.
I actually was going to start a new thread about making Karma a currency. Happily, I searched this thread first.
I would also add one item to the list. Make all comments cost Karma. If you are saying something that you do not think has the potential to be upvoted, just don't say it.
I would suggest one additional thing, which is a little bit more invasive. After a user submits a comment, show a confirmation question like "Are you sure you are making a positive contribution to the conversation? [Yes] [No]"