At least for me, the Loeb Classical Library is most helpful not for the facing English translation, the introduction, or the notes; helpful as these are. It is the widely available and mostly affordable access to an original language text. The rest is the cream. And despite their reputation among “real” classicists as texts for hacks and grad students, they are inestimably helpful to, for instance, biblical and theological students, or to priests and hobbyists, or indeed to hacks and grad students.
But alas, there is nothing like this for the study of historical theology, excepting those few early fathers found in the Loeb (Whose use is rather negated by the fact that one must purchase half a shelve’s worth of books just to get The City of God or Philo’s works). There are, however, similar works in both German and French; namely the Fontes Christiani and the Sources Chrétiennes. What’s more — and here I mean the Sources Chrétiennes because I don’t know about the FC — these very often are not just a text but a critical text with apparatus and sometimes commentary. This allows for them to be useful for academic citation.
Now English does have a series that produces texts like this, the Oxford Early Christian Texts, but not only are these texts obscenely expensive, the series makes no aims whatsoever at being a patrology.
I would at least like to assert, though, that it would make a great foundation with which to produce a Patrologia Maior. Forget doing an exhaustive patrology, hell, even a hand-held bi-lingual edition of Minge would work even if it is much less than desirable.
I can’t be the only person who thinks this, right? How handy would a “Loeb” Patristics Library be? Indeed something like the whole combination of Loeb Classical Library, Cambridge Commentaries, and Oxford Classical Texts would be pretty sweet. And how could such a thing not but increase interest in studying patristics in the original languages?