"You have the SSPX problem of taking decrees and doctrinal pronouncements from the people that they theoretically recognize as the Pope have to pass in review in front of the Superiors of the Society who decide which of them are in accord with Tradition and which are not. This was the idea of sifting – the French word was cribler – they do the sifting. And, that seems like a pretty dead end to me, because I don’t see that anywhere in a Catholic theology book. We know that the Church can’t defect. It’s contrary to the nature of the Church. But we know that the Church does not cease to exist when you don’t have a Pope for a while, not even for a long time. There’s no theologian who says that."