I have seen the kinds of arguments that result when faithful witlesses and apostates get on those sites. The apostate will usually refute something from the Washtowel, often using the Bible itself. The witless will use stock arguments, usually from the False Reasoning Book, to rebut it. Invariably, those arguments are so full of holes that apostates have no trouble rebutting them. However, the witlesses refuse to quit--they simply repost their stock arguments about it.
You cannot win the argument against the witless. About all you can do is make them look so stupid that no one reading it will believe in what they have to say.