And I have maybe 85% credence that someone is downvoting old comments of mine (in bulk but fairly slowly). It's not hard to guess who, if so.

It seems to me that LW moderators should give serious consideration to undoing all the past votes of Eugine's known accounts, if only to reduce the motivation to do what he does. (And implement a not-too-low karma threshold for downvoting, but that involves actually changing the code rather than "just" tweaking things in the database[1].)

[1] Anyone who has looked at how the DB is organized will understand why I put "just" in quotation marks there.