I heard once on the radio*, they were talking about how in the eighties there was that whole period of urban flight. And then some of the folks that moved out to the suburbs decided to move back since they were spending all their time commuting. But after they moved back, their stress levels were still high. And it turned out that they lost that time alone - the commute - that one period of every day where they were away from the immediate demands of others (except the other commuters).
I am a born multi-tasker. I tend to have rows of programs open when I work - and I am only marginally better when not working. I read during commercials and knit during the show.
And yet - as many say - I often come up with great ideas in the shower. So, possibly, if I give my brain enough space, I actually work better. Instead of thinking I am better an more productive for doing part of two (or six things), I could do one thing - or nothing for a bit.
*My googling skills were not able to turn up any supporting documentation, so make of that what you will.