Scott Windsor is cool with private interpretation. Why aren't you?

Mr Windsor, thanks for the time!
I just used the Eph 2 post as an example of what I was trying to bring out back at the Beggars All combox. Just to rundown for those who might not have read all that interaction...

Over here at BA, we make various arguments from the Bible against RC dogma. RCs come along and comment, and one of their principal arguments against our position is "That's just your private interpretation. We have an infallible interpreter, and so we can be sure that what the Magisterium says is the valid interp of the Bible, since she is the church founded by Christ and the gates of Hell won't prevail against her. Since you just have your private fallible interpretation, I don't need to pay attention to your contentions".
He was honest enough to admit, in the 02Nov post, that his apologetic blogging is not submitted to the RCC either (but that he will heretofore make his priest aware of it). I thanked him for his honesty and pointed out that the logical outworking of this fact is that he does not consider this common argument made by other RCs at various times in the past (I am unaware whether Mr Windsor has ever used this ridiculous argument) to be a valid one. I used the Eph 2 post as an example of that, asking Mr Windsor whether he would use that argument to overturn what I'd said in the 2007 post on Eph 2. It looks like the answer is mostly no, but I am a bit quizzical on Mr Windsor's request for specifics (see the end of his post).
Have you really never seen that argument used before? Not even once? Never listened to, for example, any of the many debates that James White has done with RCs over the years, wherein the RC apologists use that argument over and over?
Take a couple of examples, and please know that I am trying to be very specific in my question. I don't want to get into an extended debate on the subject matter itself, but rather on the principle of "he was only speaking as a private theologian/individual, not for the entire Church" nonsense.

"Moreover, I have heard that certain persons have this grievance against me: When I accompanied you to the holy place called Bethel, there to join you in celebrating the Collect, after the use of the Church, I came to a villa called Anablatha and, as I was passing, saw a lamp burning there. Asking what place it was, and learning it to be a church, I went in to pray, and found there a curtain hanging on the doors of the said church, dyed and embroidered. It bore an image either of Christ or of one of the saints; I do not rightly remember whose the image was. Seeing this, and being loth that an image of a man should be hung up in Christ's church contrary to the teaching of the Scriptures, I tore it asunder and advised the custodians of the place to use it as a winding sheet for some poor person. They, however, murmured, and said that if I made up my mind to tear it, it was only fair that I should give them another curtain in its place. As soon as I heard this, I promised that I would give one, and said that I would send it at once. Since then there has been some little delay, due to the fact that I have been seeking a curtain of the best quality to give to them instead of the former one, and thought it right to send to Cyprus for one. I have now sent the best that I could find, and I beg that you will order the presbyter of the place to take the curtain which I have sent from the hands of the Reader, and that you will afterwards give directions that curtains of the other sort--opposed as they are to our religion--shall not be hung up in any church of Christ. A man of your uprightness should be careful to remove an occasion of offence unworthy alike of the Church of Christ and of those Christians who are committed to your charge." - Epiphanius (Jerome's Letter 51:9)

"Others of them employ outward marks, branding their disciples inside the lobe of the right ear. From among these also arose Marcellina, who came to Rome under the episcopate of Anicetus, and, holding these doctrines, she led multitudes astray. They style themselves Gnostics. They also possess images, some of them painted, and others formed from different kinds of material; while they maintain that a likeness of Christ was made by Pilate at that time when Jesus lived among them. They crown these images, and set them up along with the images of the philosophers of the world that is to say, with the images of Pythagoras, and Plato, and Aristotle, and the rest. They have also other modes of honouring these images, after the same manner of the Gentiles." (Irenæus, Against Heresies, 1:25:6)

"These men [heretics], moreover, practise magic; and use images, incantations, invocations, and every other kind of curious art." (Irenæus, Against Heresies, 1:24:5)

"the law itself exhibits justice, and teaches wisdom, by abstinence from sensible images" - Clement of Alexandria (The Stromata, 2:18)
"familiarity with the sight disparages the reverence of what is divine; and to worship that which is immaterial by matter, is to dishonour it by sense." - Clement of Alexandria (The Stromata, 5:5)
"Works of art cannot then be sacred and divine." - Clement of Alexandria (The Stromata, 7:5)

We cite these as evidence against the RC contention that the church has been RCC throughout history. RCs most typically respond with "he was just speaking as a private theologian". Do you consider that a valid response? If so, why, since the question is what the Church has believed throughout history, and isn't that response simple special pleading? If not, can you explain the disunity and fragmentation that this disagreement displays in the ranks of RCC?


Now, on the other topic, your response to my contention with respect to Eph 2, since Paul goes on to mention circumcision, that means that v 10 - "For we are his workmanship, created in Christ Jesus for good works, which God prepared beforehand, that we should walk in them" is a command to perform the works of the Law, correct? Why does not the RCC do so, then? When was the last time you offered a grain offering? Were your sons (if you have any) circumcised on the 8th day? How have you solved the problem that has long vexed the Jewish people, that you don't have a Temple in which to perform the sacrifices? Why isn't Yom Kippur a big, big deal on the RC calendar? Why is it OK (a propos) to bow down to graven images now even though Joshua wouldn't've permitted Jews to bow down to images of the dead (but no doubt sainted) Moses?
And could you please answer another of the original challenges? - our RC friends are saying that justification is at least PARTLY due to works, ie, justification is not by faith alone, in light of your statement No Catholic argues that works of the Law justify. It sounds like you are saying precisely that. Clarification would be appreciated.