Indeed they can't, but they are still different things; it's reasonable to have different attitudes towards #1 becoming a community norm and towards #2 becoming a community norm; and what encourages #1 and what encourages #2 might be different.
Encouraging #1 unavoidably encourages #2 too, because it provides plausible deniability. I have no idea how bad it could get.
You're right -- I should have said "complaining and providing names". Sorry about that. I shall edit my comment to clarify.
This is what I meant by the strawman, thanks for catching it.
What do you think anyone concerned can actually, realistically, do to change the system?
Take all the people who complain about abuse, and brainstorm what a good system would be like. Make a post about the proposed solutions and have lw people vote. Find a programmer who can do it for free, or pay for one. Ask permission from an admin.
I proposed a solution in an open thread, but can't find it. The idea was that most mass downvoting happens within a short time period in an angry mood, so limiting the amount of votes one can give within a time period to a particular person could be a solution. People seemed to like it based on the upvotes. It might not work for this particular situation we have here, though, but would at least make mass downvoting a nuisance for the culprit.
I'm not sure what the reddit platform allows for.
Ask permission from an admin.
This is where I foresee the difficulty, if the change being proposed isn't very small and simple and unequivocally an improvement.
limiting the amount of votes one can give within a time period to a particular person could be a solution.
Yes, that seems like it would help -- though, as you say, maybe not in this case which seems to be either a longstanding grudge or an attempt to intimidate people away from expressing certain sorts of views on LW. Your proposal does have the advantage of being small and simple.
I'm just tired of the signal pollution, and would like to be able to use karma to honestly appraise the worth of my articles and posts, without seeing 80% of my downvotes come in chunks that correspond precisely to how many posts I've made since the last massive downvote spree.
EDIT to add data points:
Spurious downvoting stopped soon after I named a particular individual (not ALL downvoting stopped, but the downvotes I got all seemed on-the-level.)
One block of potentially spurious downvoting occurred approximately one week ago, but then karma patterns returned to expected levels. I consider this block dubious, because it reasonably matches what I'd expect to see if someone noticed several of my posts together and disagreed with all of them, and did not match the usual pattern of starting with the earliest or latest post that I had made and downvoting everything (it downvoted all posts in a few threads, but not in other threads), so I'm just adding for completeness.
Spurious, indiscriminate downvoting started up again approximately half an hour ago on Sunday (12/1/2013), around noon MDT.
Edit: And now on Tuesday, 12/3/2013, at 10 AM, I'm watching my karma go down again... about 30 points so far.
Edit: And now on Saturday, 12/14/2013, at 2 PM, I'm watching my karma go down again... about 15 points so far, at a rate of about 1-2 points per second.