I think the ITT may test more for personal experience than ability to model. For instance how well would this group of Christians and Atheists do trying to imitate Muslims, Buddhists, Hindus, Shintoists, Zoroastrianism, and other even less well-known religions in the Western world? Most English speakers have some familiarity with a branch of Christianity. How many have explored Shaamanism (I haven't)? Many atheists have gone through the motions of Christianity or some other religion in the past and have a comparably easier time writing about how that religious behavior and belief feels from the inside.

How do we separate the ability to understand and model other beliefs from the measurement of prior experiences? How do we eliminate the effect of writing/storytelling ability? MOAR SCIENCE NEEDED (imho). I love the idea of this project and hope you continue it. I may volunteer next time.