I've so much enjoyed Adam Barnette's blog on the 1965 Missal. One hardly hears about this liturgy at all and yet, as he points out again and again, it is one that follows most directly from Sacrosanctum Concilium (1963), so it is reasonable to see that as most reflective of the prevailing opinions concerning the letter and spirit of the mandate for reform.
However defensible most of the changes are, it seems clear that there were missteps, perhaps some that doomed the whole project. In particular, I've littered up his blog with obsessive comments on what strikes me as most strange about this Missal: the retention of Latin in propers and the introduction of English in the Ordinary.
See, for example, this page at the Pax Domini and before the Angus...err...Lamb of God. As I wrote on his blog, this strikes me as big strategic error, one that neither satisfies the vernacularists nor calms the fears of the trads of the time that the Mass was being mangled. Even today, in regular parishes, there is very little prospect of putting propers in Latin anytime soon (unless sung exclusively by the schola) but there is a growing demand for the Ordinary to employ Latin (I've yet to hear anyone cite 1965 as the precedent against Latin Ordinary, so I can only hope the wrong people aren't reading this blog).
Now take yourself back to 1965. Imagine yourself having grown up under the old Mass--not understanding too much of the propers (at least not without reading them) but feeling great comfort at the week-to-week repetition of the familiar things: Kyrie, Sanctus, Gloria, Sanctus. Then one day you show up and the liturgy looks and feels the same except for the parts that you have loved since childhood. Instead of Agnus Dei you are given "Lamb of God." One could see how this would strike a sense of alarm in Mass goers.
Now imagine the reverse, with propers in English but retaining Latin in Ordinary. This seems that something that would have pleased many (provided the translations were good) and calmed fears too.
I'm probably making too much out of this, but this whole period of liturgical history has always struck many people as mysterious in every way, and so we are always looking for clues as to what happened and why. I'm just wondering if Adam might have stumbled upon a possible explanation , or at least a partial explanation, for the liturgical instability of the period.
What I mean is this: is it possible that had the 1965 Missal been more sociologically viable that there might never have been a 1969-70 Missal? I don't know. But it is a question worth asking. In any case, it makes for fascinating study (and clearly I need to do more).