I try to stay out of the appreciation threads. I've myself been targeted by haters badmouthing me and attacking me, even after we've been blocked one way or another. Nowadays I try to put it forward to the user and confront them directly if I have an issue with them.
I've made some anonymous posts, but those are more based on a pattern of behavior than a specific user, tho inspired by someone. I do however see enablers being a bigger issue and most of my anonymous posts have these included as a part of the post. I've been attacked by enablers when confronting someone directly and even on my anonymous posts, to a length where I also had several people flagging a half dozen of my posts. There wouldn't be bullies and harassers around if they no longer had an audience of enablers telling them how lovely they are when they whine about being confronted with their crap.
