Look at you, Joe, getting all RC up in here. Lol! I had many of those same worries, which I worked through. First, you haven't even seen the actual argument. If you still have the same worries after looking at it, then that will be good to know. It's a work in progress. Second, and more substantively, you worry that the commitments aren't logically independent. The argument doesn't assume independence. It uses conditional probabilities. There's a probabilistic penalty applied to the conjunction not because the claims are independent but because they're not related by logical entailment. You also raise the issue of them being strongly probabilified by papal authority. But even if the probability of tradition and magisterium and infallibility given papal authority is something like 0.95, the conjunction penalty still applies because 0.95 is less than 1. Further, "papal authority" as a basic supposition is what needs justification, and the historical evidence calls this into question. You say it's a "modest basic posit," but it's not. It's the very claim under dispute. Third, you worry that coherence is an advantage over "pick and choose" Protestantism. But that coherence is bought at the price of construction. That is, if the Magisterium has final interpretive authority over Scripture and Tradition, plus its own past declarations, then the system will appear coherent regardless of whether the claims are true. What evidence within the Catholic system could falsify the papal infallibility that the system assumes and relies on? Any counterevidence gets reinterpreted by the authority whose claims are being questioned. That's a hoot and a holler from full-blown unfalsifiability. Also, Protestantism isn't "pick and choose." It's Scripture judging tradition, which is a principled criterion. We're not arbitrarily selecting doctrines. All are tested against the infallible norm of Scripture. That's not incoherent. It's a different model of coherence, one that has an external check instead of something like a self-validating circle. Fourth, you say logically stronger hypotheses gain more from successful predictions. That is a good Bayesian point. Riskier and more specific predictions do get a boost in confirmation when successful. But what successful predictions does Catholicism make? Well, I won't walk through them all, but going off what Joshua Sijuwade has argued in sections 4 and 5 of his paper "The Identity of the Church," the Catholic system's predictions fail. So we don't get the likelihood boost you're gesturing at. However, Protestantism predicts a fallible church guided by infallible Scripture would show the pattern we actually observe. The broad agreement over first degree doctrines and the messiness over secondary matters is what we predict and observe. So I'd say the predictive power point cuts against Catholicism when you look at the actual historical evidence.