The Eucharistic Mystery of the Orthodox Church lies not in keeping the Anaphora - the Eucharistic Canon containing the account of salvation history (especially in St. Basil's Liturgy), the institution of the Holy Supper and culminating in the change of the elements - something secret, said only by the celebrating priest for himself, but rather in the wholeness of that change of the gifts into the Body and Blood of Christ and our becoming fully intimate communicants in them. Intimacy and communion implies true knowledge of those with whom we are in intimate communion, and the Holy Anaphora imparts to us that knowledge. By hearing it we take it into ourselves, preparing us to bring ourselves into union with God and with each other.
We all have heard icons referred to as "windows into heaven". By seeing them with the physical eyes and contemplating them, we are drawn into communion with Christ and the Saints and the events depicted upon them. How then should it not be the same with the prayers of the Anaphora which are verbal icons, that by hearing them with the physical ears and contemplating them, we enter into communion and participate in God's oikonomia of salvation history which is depicted in words?
Truly, we should no more think of doing the Holy Anaphora silently than we would of covering up icons with a curtain.
Metropolitan Isaiah of Denver publishes his liturgical encyclicals on the Metropolis website. In one of these, dated 2 August 2008, can be found the following, beginning at the top of page 3:
k. In accordance with the decision of the Eparchial Synod, all prayers are designated to be "Recited by the Priest." The distinctions of "Silently," "Quietly," and "In a low voice," have been suppressed. By directing the Priest to "Recite" the prayers, it is understood that he is allowed the pastoral freedom to say them loud enough so that the faithful can hear them if he deems this to be appropriate in his own parish. He may likewise, also for pastoral reasons, recite certain prayers "Inaudibly."
Speaking the Anaphora aloud is one way to help make the Church truly the place where theosis is made possible, human beings going along the journey to becoming gods by grace, doing so by *actively participating* in the iconic theology of hearing the Holy Anaphora aloud and of seeing the actions of the Offering, just as they see the Saints and the Feasts in the painted icons with which we are all very familiar.