I now see what you mean, and I would still offer a correction, which I thought I could easily assume and agnostics and atheists would know: nobody doubts that Protestantism is a break from Catholicism: history, which shows us that, only underscores, if it does not prove, my point. Whatever else the RCC offered and offers, that break–which produced a roll of the die, perhaps dice (Edwin would know the number) within decades–already began to generate the differing and contradictory claims and counterclaims which no rational person could possibly entertain as being a choice of true religion, a term hotly contested in the sixteenth century.
Again, while there are many, many astronomy departments, all are united in rejecting astrology (say) and in sharing and refining methods and in pursuing the same objective results. It thrives on conflict and disagreement, but that is creative and astronomers don’t fly off to deny astronomy and recreate everything, however radically new or true their theories. Astronomy absorbs change, even progress: it does not go spinning into dozens of distinct and disagreeing sects. If it did, it would, rightly, loose credibility as a way of knowing and believing.
I did not make the claim you put into your edit, though I agree with it: nothing at all from an intellectual point of view prevents evangelicals, for example, from coming, and many prominent ones are, into the RCC. Lots of reasons for this: no committment to church as such (rites and rituals wide open), so much of the RCC is based on the NT, and their version of Bible Christianity leads to Rome often enough: they were the only identifiable religious group to stand with the RCC on partial-birth abortion (read Robert George in First Things).
God bless.
