Yeah, that one is not very obvious. Think of it like a warning: "Don't quote me on this, because if you do, you might find yourself repeating incorrect information."
A literal command of "don't quote me because I'm telling you something I shouldn't" would be something like, "Off the record, this is what happened." And yeah, that would be silly to say on the internet.
I would say that the literal aspect is the same no matter how you interpret it. It's just that jacquesm guessed the wrong reason for not quoting. It's still a command.
