Unanimous consent is a bit of a special term. It means that the Church has come to an agreement on a specific teaching.
UC is indeed a special term, and is referring to the premise that the “Fathers” were unanimous in interpretation of Scripture on some things, and thus the Holy Fathers, “are of supreme authority, whenever they all interpret in one and the same manner any text of the Bible, as pertaining to the doctrine of faith or morals..” (POPE LEO XIII, PROVIDENTISSIMUS DEUS http://www.vatican.va/holy_father/leo_xiii/encyclicals/documents/hf_l-xiii_enc_18111893_providentissimus-deus_en.html) and, therefore, it is permitted to no one to interpret the Sacred Scripture contrary to to the church or the unanimous consent of the Fathers. (V1, Ses. 3), and thus the required oath in the Tridentine Creed contained in the papal bull Iniunctum Nobis, “Neither will I ever take and interpret them otherwise than according to the unanimous consent of the Fathers.” (http://pages.uoregon.edu/sshoemak/323/texts/trent.htm, http://www.preces-latinae.org/thesaurus/Symbola/Tridentinae.html)
But which unanimity is not as in a papal conclave, but this “unanimous consent” of the Fathers came to be interpreted to mean unanimity even when there is dissent.
No, and nor has it been infalliably affirmed.
But it is defended as if it were infallible, while as there is no infallible list of what all church fathers consist of, or of all infallible pronouncements, not everything is clear as to what is infallible.
The basis for it goes back to Apostolic times, but it was confirmed at the Council of the Lateran in the 7th century.
By basis i was not referring to the assertion of one side of Tradition over another by a council, but ultimately to the real premise behind assurance of the veracity of the claims of Roman Catholicism will .
Which assurance, as said, does not rest upon the weight of Scriptural warrant (which source is disallowed as providing real certitude of Truth), though that may be invoked, but upon the premise that Rome is infallible whenever she speaks in accordance with her infallibly defined scope and subject-based formula (thus rendering her declaration that she is infallible, to be infallible). And upon which premise she can define history and Scripture as supporting her, though she rarely infallibly defines texts of Scripture, and the reasons and arguments behind an infallible decree are not necessarily infallible themselves.
“But it is defended as if it were infallible, while as there is no infallible list of what all church fathers consist of, or of all infallible pronouncements, not everything is clear as to what is infallible.”
Actually, there is a list. And no, Perpetual Virginity is not on it. It is defended as dogma - official teachings of the church, but not as infalliable dogma, as her assumption is.
“Which assurance, as said, does not rest upon the weight of Scriptural warrant (which source is disallowed as providing real certitude of Truth”
Nonsense, the argument rests that adelphoi is not limited to biological brothers. And nor does the Greek limit itself in that use. Perpetual Virginity is confirmed by the teachings of the early church fathers and does not contradict scripture. Tradition must fit into the bin, so to speak.