I hope this says what I wanted it to say:
Right but recall that I didn't propose this for LW in general, but a different forum or section. People can earn their LW karma elsewhere. But let us for the sake of this exchange suppose here we make this a general rule.
Your interpretation was an interesting question in itself. So please talk criticism of this modified idea!
Okay, in regards to the misinterpretation:
The reverse is happening precisely because there are so many new users who are voting. I'd say that the way LW started out could be used as an estimate of what that would look like. It was very rare for a comment to reach as many as 5 upvotes, and if you see an old comment that has more than that, most likely it had help from someone more recently upvoting it.
Obviously, it would not be entirely the same, and I would place more weight on the up and downvotes being more accurate if this were put into place now, but it would make it much more difficult to get to that point.
The recent implementation of a -5 karma penalty for replying to comments that are at -3 or below has clearly met with some disagreement and controversy. See http://lesswrong.com/r/discussion/lw/eb9/meta_karma_for_last_30_days/7aon . However, at the same time, it seems that Eliezer's observation that trolling and related problems have over time gotten worse here may be correct. It may be that this an inevitable consequence of growth, but it may be that it can be handled or reduced with some solution or set of solutions. I'm starting this discussion thread for people to propose possible solutions. To minimize anchoring bias and related problems, I'm not going to include my ideas in this header but in a comment below. People should think about the problem before reading proposed solutions (again to minimize anchoring issues).