(Couple of side notes inspired by your edit.)

I considered asking for people's credence in each claim with probability polls, but reckoned that'd discourage responses, due to the extra effort needed to ensure coherence. (With 1 vs. 7, for instance, one would also have to think about the probability that neither claim's true.)

When distributing the pairs across the lists, I had R flip six virtual coins to decide whether to swap the places of each pair after I'd written them. So it should be nice & random, making second guessing unnecessary...although I guess no one else can be 100% sure I'm telling the truth here!