And actually, praying the rosary during mass could be considered a liturgical abuse because you are adding your own private devotion to the Mass. What’s the difference between praying the rosary and holding your hands in the orans position during the Our Father? Maybe that person is charismatic and they normally pray with their arms extended like that. There’s nothing wrong with using that position for prayer outside of Mass.
But we still say that it shouldn’t be done during Mass because there are rubrics covering not just what the priest does, but also what the laity do.
The rosary is a private devotion, and should be done on private time (as in not during public worship, which is what the Mass is). The Mass is given to us by the Church as is, meaning that
neither the priest nor the laity can add or subtract anything from it.
If you’re busy praying the rosary, are you really paying attention to what’s going on? Fully and actively? How can you listen to Jesus as the Word when you’re not paying full attention? Or the homily, as explaining the Word to us? Even the hymns and chants are a part of our
public and
communal worship. If you’re busy praying the rosary, you mine as well not even be there because you’re separating yourself from the community.