I still disagree... You should let your users decide for themselves whether or not an opinion is good or bad. You created a system that allows users to express their opinions on opinions, with the community accordance votings. By interfering with opinions, you remove the usefulness of the community accordance percentage. Because community accordance isn't just a stat. It's a tool. If people like or don't like an opinion, they will use their own judgement and rate the opinion +1 or -1. If an individual repeatedly gets bad opinion ratings on pratically everything, then, I believe you should monitorize this person, warn him/her if needed, see if the person is a troll and then use your moderation powers... Simply put, I think a moderator should not only moderate but also be moderate. :P
If you are too strict, people will simply go elsewhere even if they are not being moderated themselves. It's good to see a cop once in a while as you walk back home late at night, but it's not the same when there's a cop on every corner, right?
Besides... Let's say one day OpiWiki becomes very popular and you get hundreds of thousands of views everyday ( or maybe more ). You won't be able to keep up anyway. Not with tiny, insignificant comments such as "he's the worst". Even if you had an army of mods, you wouldn't be able to deal with them. You will have to focus on the extremes only.
I think we've all been idiots who couldn't form solid arguments at some point or another during our life! When I was 14, I was an idiot for sure. But, thanks to interaction with other people (including on the internet), I think I evolved and became a better person. I'm pretty sure it's the same for most people who grow up. Interaction is the key. If idiots are not confronted by smarter, wiser people, they will remain idiots... Give the poor folks a chance! ;)