“As the texts that may be rendered in music, and the order in which they are to be rendered, are determined for every liturgical function, it is not lawful to confuse this order or to change the prescribed texts for others selected at will, or to omit them either entirely or even in part, unless when the rubrics allow that some versicles of the text be supplied with the organ, while these versicles are simply recited in the choir. However, it is permissible, according to the custom of the Roman Church, to sing a motet to the Blessed Sacrament after the Benedictus in a solemn Mass. It is also permitted, after the Offertory prescribed for the mass has been sung, to execute during the time that remains a brief motet to words approved by the Church.”
searchable PDF of Hayburn
And unfortunately rather widely adopted in trad land too, sad to say.widely adopted in Novus Ordo land
For those wishing to use alternatim practice, I suggest adopting an even older Catholic liturgical attitude (widely adopted in Novus Ordo land):
do whatever the heck you want.
widely adopted in Novus Ordo land
And unfortunately rather widely adopted in trad land too, sad to say.
since no rites really exist anymore that have rubrics dictating alternatim practice
I also wonder if the Roman Curia were conservative, or just too irreligious to make the time for tropes and extra prayers.
4. This new rite alone is to be used unless approval of the practice of saying Mass differently was given at the very time of the institution and confirmation of the church by Apostolic See at least 200 years ago, or unless there has prevailed a custom of a similar kind which has been continuously followed for a period of not less than 200 years, in which most cases We in no wise rescind their above-mentioned prerogative or custom. However, if this Missal, which we have seen fit to publish, be more agreeable to these latter, We grant them permission to celebrate Mass according to its rite, provided they have the consent of their bishop or prelate or of their whole Chapter, everything else to the contrary notwithstanding.
5. All other of the churches referred to above, however, are hereby denied the use of other missals, which are to be discontinued entirely and absolutely; whereas, by this present Constitution, which will be valid henceforth, now, and forever, We order and enjoin that nothing must be added to Our recently published Missal, nothing omitted from it, nor anything whatsoever be changed within it under the penalty of Our displeasure.
6. We specifically command each and every patriarch, administrator, and all other persons or whatever ecclesiastical dignity they may be, be they even cardinals of the Holy Roman Church, or possessed of any other rank or pre-eminence, and We order them in virtue of holy obedience to chant or to read the Mass according to the rite and manner and norm herewith laid down by Us and, hereafter, to discontinue and completely discard all other rubrics and rites of other missals, however ancient, which they have customarily followed; and they must not in celebrating Mass presume to introduce any ceremonies or recite any prayers other than those contained in this Missal.
To participate in the discussions on Catholic church music, sign in or register as a forum member, The forum is a project of the Church Music Association of America.