> "You can get 20 rep by asking or answering a single — literally, one — half-decent question"

So what you're saying, is that any spambot could thwart the system easily, and the arbitrary restriction is silly, and mainly just means this will not take off beyond fanatical SO users (Which is fine, if that's their aim).

IRC has developed fantastic ways to keep out spammers and idiots. And the methods don't usually involve things like this.