I'd use the only tool we have to sort theories: Occam's razor. 1. Weed out all the theories that do not match the experiment — keep both in that case. 2. Sort them by how simple they are.

This is what many do by assuming the second is “over-fitted”; I believe a good scientist would search the literature before stating a theory, and know about the first one; as he would also appreciate elegance, I'd expect him to come up with a simpler theory — but, as you pointed out, some time in a economics lab could easily prove me wrong, although I'm assuming the daunting complexity corresponds to plumbing against experiment disproving a previous theory, not the case that we consider here.

In one word: the second (longer references).

The barrel and box analogy hides that simplicity argument, by making all theories a ‘paper’. A stern wag of the finger to anyone who used statistical references, because there aren't enough data to do that.