I guess Pius XI is a pompous "novus ordite" as well since I'm only repeating his teaching. I wouldn't be surprised if you think he was a modernist though. 

Every time someone says something like the above comment, it turns out that the pope was teaching some minor aspect in which the person was correct, like the popes asking for participation in the mass from the zombies that just went to mass because their grandmother, wife, husband, the kids school, required them to go....... OR the person is misinterpreting what the pope said, interpreting it according to his own desires. Notice the OP posted no quotes from Pius XI.

Every time someone says something like the above comment, it turns out that the pope was teaching some minor aspect in which the person was correct, like the popes asking for participation in the mass from the zombies that just went to mass because their grandmother, wife, husband, the kids school, required them to go....... OR the person is misinterpreting what the pope said, interpreting it according to his own desires. Notice the OP posted no quotes from Pius XI.

Here is your quote from Pius XI:

"In order that the faithful may more actively participate in divine worship, let them be made once more to sing the Gregorian Chant, so far as it belongs to them to take part in it. It is most important that when the faithful assist at the sacred ceremonies, or when pious sodalities take part with the clergy in a procession, they should not be merely detached and silent spectators, but, filled with a deep sense of the beauty of the Liturgy, they should sing alternately with the clergy or the choir, as it is prescribed. If this is done, then it will no longer happen that the people either make no answer at all to the public prayers — whether in the language of the Liturgy or in the vernacular — or at best utter the responses in a low and subdued manner."


Divini Cultus On Divine Worship (adoremus.org)

Here is your quote from Pius XI:

"In order that the faithful may more actively participate in divine worship, let them be made once more to sing the Gregorian Chant, so far as it belongs to them to take part in it. It is most important that when the faithful assist at the sacred ceremonies, or when pious sodalities take part with the clergy in a procession, they should not be merely detached and silent spectators, but, filled with a deep sense of the beauty of the Liturgy, they should sing alternately with the clergy or the choir, as it is prescribed. If this is done, then it will no longer happen that the people either make no answer at all to the public prayers — whether in the language of the Liturgy or in the vernacular — or at best utter the responses in a low and subdued manner."


Divini Cultus On Divine Worship (adoremus.org)

Read the series on the dialogue Mass and laity participation by Carol Byrne starting here: A Plea for Silent Participation in the Liturgy - Dr Carol Byrne (traditioninaction.org)
it answers all of the questions you could ever come up with.

P.S.- I use to give away paperback full Sunday missals (with the Propers for every Sunday) to newcomers that could not afford a missal and I would tell them that if they had any questions, to feel free to come ask me. All of them, without exception  would come to me and tell me that they could not keep up with the mass, that they would get lost as to where the priest was. I then explained to them that the priest goes on with the mass while the choir is singing, that if they wanted follow the priest they had leave the singing to the background and continue with the prayers in the missal, that one either sings or they pray the missal. I meditate on every word of the missal, I am oblivious to everything around me, I am in conversation with God through the saints and Our Lord Jesus Christ. In my experience the people who push for singing and verbally responding are the ones that like to sing, and they never read the missal. I do not personally see that as participating in the mass, but, to each his own.