Did you ever think you might have the wrong approach?
I understand that some problems are easier to solve with brute force. Brute force tends to be exponential, though, so as the project grows, the amount of brute force required grows faster. How big does something have to get before the amount of brute force becomes prohibitive?
Ask the RIAA, they've found the edge.
To me, when I see a brute force approach, I think "Oh! Look! A puzzle!"
To me, word filters aren't the right solution. People are going to express themselves regardless of what words you filter, and there are quite a few people who are more offended by the filters than by the language. For example, someone saying "the dumbfuck totally reamed me up the ass with a cactus when he ditched" is fine by me. When some twelve-year-old starts spamming, it doesn't matter whether he's spamming homophobic swears in caps or just a large number of random symbols. Either way, he's a nuisance in a way that my potty-mouthed friend is not.
To me, a word filter is a desperate attempt to cover asses, not an attempt to actually solve any kind of problem. That's the problem with a brute-force approach: it's usually treating symptoms, not diseases. Dying of cancer but with wonderfully clear sinuses is still dying.
The issue here is that the disease is not one that actually relates to chatting. In fact, it has many symptoms endemic to the game world that have nothing to do with chatting. (Hah! I used "endemic" properly! HA HAHAHA! Well, I can cross that off my list...)
What is the disease?
Maybe it's lupus!
Hee hee... no, actually, lupus is a pretty good analogy. Lupus is an auto-immune disorder that causes the body to attack itself. That's pretty much what MMOGs are doing: some bits of the body (certain players) are viciously interfering with other bits of the body (everyone who is not a dick).
The question is not "why is player A griefing player B". We already know why: players are dicks. The question is "what design would make player A unable or unwilling to grief player B without reducing the fun for either of them?"
I think it has to do with population density, and I've got a lot of little theories on exactly how and why... but what do you guys think?
Finally! A case of lupus!