I have often stated in the last couple of years that dialoguing with RC Apologists in somewhat superfluous. Why? Because the only one really qualified to speak for Rome is the Magisterium itself. Unless the Magisterium speaks no RC Apologists really is worth listening. It is nice to know that a prominent internet RC Apologist recognizes this fact. This is what he says:
While I can appreciate the desire to set good standards in apologetics, most of what we do on this board is colloquial apolgetics and quite frankly NONE of us is qualified to set any standards in defense of the faith. Only the Magisterium can do that and so far, the hierarchy has viewed the diversity of Catholic lay apologists (with some notable exceptions) with general favor.
Nobody can claim to speak DEFINITIVELY for Catholic orthodoxy except the Pope and the bishops in communion with him. We apologists in the trenches may have our disagreements but we are all working for the same end. We need to respect that and not go attacking each other needlessly. Sometimes one needs to speak out, but this should be done only for grave necessity.
So caveat lector to the Evangelical thinking of going back to Mother Church due to the convincing arguments made by an RC Apologist to her. She needs to understand that she may not be getting kosher presentation of RC doctrine.
Past Elder has a nice history view of Church History here.