I don't believe in papal infallibility. I don't believe in Scriptural inerrancy. In fact, I don't believe in any kind of infallible or inerrant authority at all. In the Church, obedience is always ascetical in nature: i.e. voluntary and non-coercive.

Orthodox who cite the ecumenical councils as infallible are fooling themselves. Even if we could legit say they were de jure infallible in themselves, we only have written records and they become subject to highly contentious text-critical reconstructions. #5 is case in point.

But papal authority, I am convinced, also remains largely a custom local to Rome and its environs. I know, I know - there are plenty of examples of other bishops ascribing special honor to Rome. But I simply don't believe Vat I is implied by the evidence out there.

The pentarchy was contextual - Rome's prestige predates it by centuries. But while Rome was enjoying such apostolic prestige, churches in Asia seemed utterly clueless that they had a responsibility to obey the Roman bishop. Cf. the Easter controversy btw. Polycarp & Anicetus.

Anyway, all this to say both Catholic and Orthodox apologetic lines are fatally flawed. I don't think anyone wins.