It seems clear that whack-a-mole banning is not terribly effective; since the main thing (I think) we want to disincentivize is unproductive mindkilled mass-downvoting, making that less effective (because likely to be undone after a while) might be worth the effort.
I doubt undoing the votes will disincentivize anyone. I suspect that mass-downvoting is either an expressive act or it's the stick in a conditioning exericise (disagree with me and watch your karma go down right now). In both cases undoing the votes many moons later is quite useless.
It wouldn't be so much a matter of disincentivizing Eugen3 etc., (though that might happen) as reincentivizing the people who were downvoted.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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