(in response to the question in witnessing Procession from musicasacra forum)
At the Potifical Mass, the Introit was sung after the Procession, not at the Procession. People who don't want to sing and don't want to be distracted in witnessing the Procession should be allowed to do so.
Many people in pews in our local parish already told me that there are too many songs they have to sing in Mass. And when my friends came to Traditional Mass, they were so relieved that they dodn't have to sing so many songs and get distracted by trying to sing all those songs, (because they've been told by the pastor and music directors that if they don't sing, they are not participating), and finally be able to focus on Mass. Many people in pews have to miss other important parts of the Mass, because they have to bury their faces in hymnals and struggle with songs. If 'hymns' are optional in Mass and not required parts, according to the Church's instruction, people should also have an option to sing or not. No Catholics should be forced to sing the parts that are not part of the Catholic Mass.
If one wanted to have more congregational singing, why not help them to sing more their parts of the Mass, "Responses" and "Ordinary parts" (especailly those in Latin as the Church instructed). They will be able to memoriaze them in time and won't need hymnals soon. And once they learn, they will be glad that they can sing the parts of the Mass, and truly participate in Mass, not just participate in singing. Whether hymns are licit or wisely chosen, hymns, especially those that are not liturgical, but individual devotional hymns, have been overused in Mass, and the Catholics in pews start to feel that more and more. I think those hymns and other songs can be sung more in adoration or in other times outside the Mass.