Unlike PF, I have no problems with this attractive title of our Lady. PF appears to prefer to confine our Lady to exclusively biblical titles; although I am not quite sure whereabouts in the Gospels he has found the title Mathetes (disciple) claimed by her. Furthermore, PF's dislike of unbiblical titles would seem to set him a teensy weensy bit at odds with the 'Orthodox' and 'Coptic' Churches, who are rather (and rather repetively) attached to the Ephesine Dogma of Theotokos. And you can't get very far in a Byzantine Liturgy without colliding with an Aeiparthenos. (Could it be that PF also finds homoousios a little over-rich for his dainty Argentine digestion? Homoiousios, perhaps, would suit him better? We all have our own personal fads!)
At the same time, I do rather feel that the title Mediatrix of all Graces is the one I would prefer to advocate with greater oomph at this present moment. One reason for this is that it is already historically so embedded in the thought of both East and West. Vladimir Lossky, the great Russian Orthodox lay theologian, wrote
"freed from the limitations of time, Mary can be the cause of that which is before her; can preside over that which comes after her. She obtains eternal benefits. It is through her that men and angels receive grace. No gift is received in the Church without the assistance of the Mother of God, who is herself the first-fruits of the glorified Church. Thus, having attained to the limits of becoming, she necessarily watches over the destinies of the Church and of the universe".
And here is a passage from the mighty Hesychast Doctor and Archbishop of Thessalonica, S Gregory Palamas:
"The All-Holy Mother of God is herself alone the boundary of created and uncreated nature, and nobody could come to God except through her ... she is the Treasury and President of the Wealth of the Godhead ... she stewards and encompasses God's graces ...".
The pre-Pacelli Western liturgical texts for the Assumption seem to me to inculcate the truth that Mary was assumed so that she could powerfully intercede for Humanity.
I drafted this a couple of days ago; I have just read Archbishop Vigano's fine piece, with which I entirely agree. But I would still like to see the Festival of OL Mediatrix of All Graces resuming its journey to the Universal Calendar on May 31 ... a journey put on hold, as I understand, by Papa Pacelli. Since I am an Ordinariate priest, it is further commended to my affections by its association with the great Belgian Cardinal who sponsored the Malines Conversations. Genuine Ecumenism!