With due regard to the above cautions about the date of Ratzinger's comments and the fact that he made them as a private theologian and not as the Pope, I am not so sure that it is beyond the pale. In fact, it already exists in the distinction between the Latin rite and the Eastern rites in communion with Rome. What Ratzinger appeared to be suggesting is that the primacy would pertain to doctrine and magisterium, the patriarchies to matters of jurisdiction and discipline (canon law, liturgy, etc.). If that is the case it would simply be expanding on a model which already exists. Even more, did it not exist for centuries before the Great Schism between East and West? I am no historian, but that is my general impression. Finally, the union of primacy and patriarchy might have seemed more appropriate when the Western church was primarily European, and no doubt it was reinforced in response to the divisive and nationalistic character of the Protestant Reformation. But now that Catholicism has become a world religion and serious ecumenical efforts are afoot, perhaps the time for a newer model has come. I am sure it would be more attractive not only to the Orthodox but also to the more conservative part of the Anglican communion.
And it would just be an extension of regional roles already developed in the Church. (Notably, the non-Latin rites in communion with Rome--- and remember the Baltimore Catechism? Not so radical really.)
I think that if the power of the geronto-communists in China were broken, things could develop there very rapidly. An Asian Patriarchate (or Eparchy) could move things along more expeditiously than waiting for all initiatives from Rome...
Veni, Sancte Spiritus! (100x)
Regarding "The Break up of the Patriarchy of the West!
Whilst the proposal may have some influence within the Roman Communion world wide, towards Orthodoxy and other non Roman Catholics, i.e. Anglican Catholics and Old Catholics, it means very little. The difference being more Uniates,rather than individual "conversions" to Rome. The problem with the Papacy and the Patriarchy is that the former has no historical legitimacy while the latter is the gift of the Ecumenical Councils which simply makes the Pope,chairman of the Latin board,as it were. If there is to be a serious attempt at unity surely the most divisive item in the Catholic Church as a whole is the Papacy?