Practically every alteration, deformation, and mutation that touched the Roman liturgy in the last century came to the faithful clergy and laity with marketing buzzwords from the Holy See like "renewal", as if the liturgy had died, or "restoration", as if the novel practices now prescribed had existed in this form at some prior point. Papa Sarto spoke of the older Roman Office in very harsh terms while calling his psalter "restitueretur." Pius XII repeated his Venetian predecessor's language after he restored Holy Week by tossing the rites, Offices, and unique ceremonies out the window for new ones. And then, of course, came the paterfamilias of "renewal", the liturgy of Paul VI, which failed to maintain even the form of similarity with the past like Sarto's psalter, which preserved some aspects of the Office for major feasts and the 150 psalm weekly schedule. Everything became new, nothing was different, and all was fixed.
The Roman Breviary went through no less than four sets of revisions in the 20th century, each leaving less the genius of the original Office than the former. What many critics of the liturgical reforms, myself included, often fail to realize is that these changes, like those to the Mass, happened gradually and under the influence of others who belonged to the places and communities where these concepts originated. The psalter of Divino Afflatu looks much more like the "Jansenist" Offices of 18th and 19th century France than it does that of Saint Pius V. In the same vein, the rubrics and schedule of Offices in John XXIII's breviary strangely resemble those of the Monastic Psalter in force three decades earlier. What were those features?
First, and most characteristic of John XXIII's Breviary, the Monastic Office underwent a reduction of supposedly quintessentially Roman feasts, both in number and in kind. Just as the 1960/2 Breviarium Romanum observes one feast of Saint Peter's Chair, so does the Monastic Diurnal of the '30s, although it previously followed the Roman praxis in observing both Rome and Antioch. Some uniquely Benedictine feasts even saw mergers in the case of saints whose historicity was deemed dubious in the early 20th century. A few alterations to the Monastic sanctoral did make clean up certain aspects of the kalendar, like transferring the octaves of Saints Benedict and Scholastica outside of Lent, where they would no longer impede the penitential season.
Second, the days of the kalendar underwent substantial revision of rank and kind. Double feasts previously enjoyed three nocturnes of four lessons each at Mattins throughout the year, except the summer when they had three. The revised kalendar provides three lessons per nocturne throughout the year and only one per nocturne during the summer. Semi-Double feasts were generally made into something equivalent to Third Class feasts in the 1960/2 Roman rite and feasts that were previously Simples found themselves more akin to John XXIII's "Commemoration" rank. The reforms did retain the traditional Semi-Double Offices for days within octaves.
One wonders why these Benedictines required a reduction in their Offices? Perhaps they needed time to buy suits and sit on liturgical reform commissions?