If I debate with someone, he tells me something like "abortion is murder", I point him to http://worstargumentintheworld.com/ and he takes the pain to read the article AND the discussion and sees why/how the domain was registered, I would claim victory in "raising the sanity waterline".

The argument authority of having a domain pointing to may (I hope it'll) increase the chance the person does at least read a bit of the page instead of discarding it, but I doubt it'll do anything into making him/her accepting that the argument is wrong behind that.