I think asking him to refute points gets to the heart of the issue -- in an environment where nobody has enough information to speak authoritatively on a subject, the people who are willing to do so anyways are advantaged. (Think about the qualifications or knowledge that one would have to have to make an informed assessment of this.) This is bad for productive discussion.

I agree that empty snark is usually unproductive, but in this case, I think there's a useful point being made. Still, always best to rephrase into non-snark. :)