What Padre Pio did is for the most part irrelevant to people who have a job or are going to school… Most people cannot pay attention adequately to two completely different things at the same time. I don’t intend to challenge what he did or didn’t do. If I am doing a task which takes minimal attention (for example, loading a wash machine, vacuuming, or doing the dishes), I can say a rosary while doing so. Likewise, while driving up a freeway where traffic is moving relatively equally. as others have noted, driving in a city is a bit different and requires a greater deal of attention. So also, attending a class, reading a text book, or doing calculations for a reserve study all require a greater degree of attention. Trying to say a rosary at the same time reduces the rosary to a mechanical bead pushing. We need to engage the rosary as a conscious prayer, not something we rattle off as if that was adequate.
The comment I made about school: we would put JMJ at the top of the page we were working on, and say a short prayer offering the work we were about to do to Jesus, Mary and Joseph; then we would pay attention to what we were doing. One’s work can be a prayer if we offer it up and intend it to be a prayer. It is not necessary to be saying words all the time.