Well, I've enjoyed the merry-go-round, but I think it's time to get off. The scenery has become monotonous.
What I've learned in this thread:
The Roman Catholic Church is the true Church of Jesus Christ because Jesus made Peter the Pope.
We know this because the Roman Catholic Church tell us that when Jesus gave Peter keys to bind and loose and told him to feed His flock it meant He was setting Peter in as the CEO of His Church and the ultimate decider of points of doctrine.
We know from Common Sense!(tm) that Peter handed those keys down to one man who did likewise so that one mortal man is the final decider throughout Church history. Oh, and the Roman Catholic Church told us.
We can safely ignore portions of scripture that the Roman Catholic Church tell us are unimportant. Like Jesus telling Peter that he shouldn't exercise dominion and authority over other believers.
Whatever the Pope and the Roman Catholic Church says is True. This means that when a Pope signed a confession that Jesus was not divine, that was not heresy until the Church later said it was heresy, at which point it became heresy. This is true of other Popes who recanted from heresy. They weren't heretical until they recanted from heresy at which point their past statements became retroactively heretical.
In summary, the Roman Catholic Church is in charge because the Roman Catholic Church says so.