para 1 Universae Ecclesiae One might have expected Universali Ecclesiae; the normal term for "the Universal Church". Universae seems to me deliberately to avoid the formulaic expectation so as to emphasise per variationem that it really is the (yes!) entire Church which is to have a richer appropriation of the Roman Rite. (I take this literally. Just as Latins would have their spirituality immeasurably enriched if they knew the Byzantine Rite better, so Byzantines will be enriched the better they know the riches of the ancient Roman Rite.)
paras 1,2,3,4: Notice how, in accordance with this same stylistic trope of variatio, the Pope is referred to differently as Summus Pontifex, Sanctitas Sua, Apostolicus Dominus. This last of these seems to me to have an early first-millennium flavour to it; I have traced the language of it back to a letter from the Emperor Maximus to Pope Siricius (384-399); and there is a whiff here of the Ordines Romani (except that later in the first millennium dominus would have been syncopated to domnus). A tiny verbal harbinger of a more First Millennium Papacy?
para 5 heic How delightful to see this unusual orthographical rendering of hic! OLD says that it is common in inscriptions. Does this mean that the official responsible spends most of his spare time with his nose in the Corpus Inscriptionum Latinarum? Let us hope that he is not too addicted to all those naughty graffiti in Pompei!
para 10(2) emanat seems to have acquired a transitive sense in the corridors of modern Rome.
para 20(c) Slightly odd. It seems to imply that if only a malevolent bishop could prevent a priest from ever saying a first EF Mass, that priest would never attain to full idoneitas.
para 21 enixe is missing from the English version. In the Latin, ordinaries are strenuusly asked to ensure the appropriate formation of clergy. But we English are so laid back that the Vatican dare not strenuously ask Anglophone bishops to ensure this provision.
para 21 providebitur. The English reads ... seminaries, where future priests should be given proper formation, including study of Latin and where pastoral needs suggest it, the opportunity to learn the EF ... The Latin says ... seminaries, in which it will be provided that future priests are given proper formation, by learning Latin and, where needs suggest it, the EF itself. I think that the Latin indicative future providebitur means "we assume they will be taught Latin because Canon Law explicitly requires that anyway ... but whether they are taught the EF too depends on circumstances." There seems to be an implication here that seminary principals may have in the past been negligent in obeying CIC 249 (on the teaching of Latin), not to mention the explicit mandate of Vatican II (Sacrosanctum concilium 36; and see Optatam totius 13). Surely not!
para 24 I presume this means that SSPX priests will have to buy birettas. And I think it means that when the Oxford Oratorians sing 1962 Sunday Vespers on Septuagesima, they will have to do it in purple ... and that they will have to keep Christ the King in October, Ascension and Corpus Christi on Thursdays, et sim..
para 25 aliquae So it appears that not all the new OF Prefaces will enter the EF wholesale. The addition of just a few will be in line with the gradual tendency to add individual prefaces, which was established in the first half of the twentieth century.
para 32 et quidem integre et Latino sermone. Vernacular translations appear to take this as meaning that the Breviary office must, if the 1962 Breviary is used, be said in its entirety from that rite ... i.e., if you don't say it all, you can't say any. This would make it illegal for Oratorians to sing Sunday Vespers according to 1962 unless they were all in the habit of saying their entire office according to 1962 .... Prime and all. But Laudis canticum of 1970 established a precedent by envisaging permitting decayed clergy sive ex toto sive ex parte retinere the old Breviary. I would take the Latin of UE to mean "and what is more*, they have the facultas [if they desire to use it] of reciting it in its entirety and in Latin".
*The normal sense of et quidem is (OLD s.v. quidem 5) "(adding a reinforcement or afterthought) And what is more ... ". ["Provided that they say it in its entirety and in Latin" would, I think, have to be "Dummodo id recitent integre et Latino sermone".]