But this raises some questions about obligation. What about Prime? If someone is praying with the breviary of Bl. John XXIII, is he obligated to recite it, seeing as it doesn't exist in the current rite and is thus absent from the current Canon Law?
And what about the "little hours," Terce, Sext, and None in the usus antiquior and Mid-Morning, Midday, and Mid-Afternoon Prayer in (the American English translation of) the Breviary of Paul VI? According to the current understanding, clerics outside of choir only have to pray one of these three at some time between Morning and Evening Prayer. Was this a relaxation of the reform or was it in effect before? Is a cleric using the 1962 breviary obligated to all three, or not?
Just wondering as I take a morning off to strain out the gnat and swallow the camel.