William Mahrt believes that the motu proprio holds out the prospects for vast gains in the area of sacred music.
It is important that when the old use is celebrated as a high Mass, the music be done well. It will have to serve as a paradigm. One such Mass in a large city with properly prepared and performed music could be a leaven for the musical practice of the whole city’s churches. There will be those who will attend this Mass regularly and faithfully; they will come to experience the orderliness and serenity they may have missed at their parish Masses; if the music is excellent, they may find a quality they have missed in their parishes as well. There will be those who will attend this Mass occasionally; they will return to their parishes with new expectations, and may have an influence on how things are done there. There will be the curious and the skeptical, who may attend this Mass once; if it does not radiate beauty and holiness, they will go away confirmed in their belief that it was right to discard it. This poses for musicians a challenge and a high expectation; why should it not, though, for its purpose is the highest a human being can seek.