From time to time I get serially downvoted. I wait for the reversal script to kick in, and it doesn't, and when I flag it, nothing happens.
It's not because the serial downvoting didn't happen, but because they can't do much about it.
Actually, I don't even know :-) I asked a Stack Exchange employee to look, but vote information is private and I can't look at it myself
...
That's all moderators can do with serial voting, really. We bring it to the attention of Stack Exchange employees if need be, and then they decide if anything needs to be done.
Fine. In that case, just make the serial downvoting script more active. Scripts can know who did what without any privacy issues.