In De Musica Sacra (1958), we read
It is for this purpose that the present instruction has been prepared. Experts in sacred music, and the Pontifical Commission for the General Restoration of the Liturgy have given advice and assistance.
In a brief Google search, I couldn’t find much about this commission. Here’s one source:
The process of reform and renewal of the liturgy was not something that came “out of the blue” but was a natural outcome of the renewal of the whole Church brought about by the Second Vatican Council. Liturgical reform itself was also not something new. It was completely normal practice for the Church to renew its liturgy. Gregory I (d. 604) and Gregory VII (d. 1085) were great liturgical reformers; Sixtus V (1588) entrusted the “reform and correcting of the liturgical books” to the new Congregation of Sacred Rites and Ceremonies; Pius X, in his Motu proprio “Abhinc duos annos” (23/10/1913) describes the condition of the liturgical rites as “squalor”; Pius X described the reform of the psalter in 1911 as a “first step”; Pius XI added an important historical section to the Congregation in 1930; Pius XII established a pontifical commission for the general restoration of the liturgy in 1948, and there were reforms to the liturgies of the Easter Vigil (1951), Holy Week (1955), a provisional simplification of the rubrics in the Breviary and the Missal (1955), and an Instruction on sacred music (1958). Among these reforms, the Decree on restoration of Holy Week of the Sacred Congregation of Rites lists three important sources of petitions for liturgical restoration: (a) liturgical experts or scholars, (b) pastors, and most important © bishops.[ii] Finally, in the period prior to the Second Vatican Council, Pius XII’s Allocution of Sept 22, 1956[iii] contains a summary evaluation of the Liturgical Movement.
I’m curious whether this commission ever did anything noteworthy in and of itself, or if it was really a backwater dicastery during its existence. Was the advisory role on De Musica Sacra the high point of the commission?