I don't even think that self moderation is appropriate in threads. Announcement threads or campaign threads needs freedom of speech incase anything related to scam.
Having a feature is good. Abusive people will try to abuse everything they have and to restrict them it does not make sense to remove or not introduce a useful feature.
Self moderated threads are useful in many ways. Once the community will become bigger, the number of trolls will grow too. Without a self moderated thread it's impossible to control the trolls if you want to focus in a discussion.
That will be a good feature in the forum but we have spent one year in the forum and we have seen how the forum participation is and from my point of view, the spamming and abusive level of the forum is minimal. And since there is no self moderated feature is not in the forum, you can report any unwanted comments to the moderators and they will switch into action and remove the trash from your topic.
One thing I like this forum is the moderators are very active to respond to complains and reports.