It's interesting that you think thatis an annoying rhetorical tactic. Instead of explicitly suggesting P, which might require you to support the proposition P, you instead sneer at the possibility that someone might think not-P.
Actually in this case my main reason for believing not P is that they haven't been successfully trolled yet. If an intelligence agency did attempt this trick then they'd almost certainly succeed, because the Wikileaks crew are mere mortals and quite capable of being fooled by a clever fake.
If any intelligence agencies are reading this, though, and feel like offering me a job in the wikileaks-trolling department I'd be happy to accept it.