I could see this as an interesting exercise during certain kinds of workshops or camps. Or during a week of low-stress, no-deadline work in the office. I can, however, see The Suits latching onto this as The Next Big Thing. And it will be about as useful in an every-day work environment as making your programming staff take support calls during their coding time - context switches cost lots of time and reduce productivity.
My understanding is that the Promiscuous Pairing idea was started by real developers working on a real project with tight deadlines. The point of the paper is that, counterintuitively, the approach worked very well _in practice_. So I wouldn't be so quick to dismiss it based on first principles.
That said, it certainly depends a lot on context. My team at work has tried full on switch-every-ninety-minutes Promiscuous Pairing a couple of times. Once, it worked really well: everyone started knowing the code much better; we got more done; we spent less time stuck and confused and more time producing quality software. Another time, it was a nightmare: everyone felt rushed and confused; it seemed like we were constantly being interrupted; we never felt like we were getting anything done.
I'm not entirely sure what made the difference. Our going explanation is that, the second time around, we had a higher baseline level of interruptions already, so the constant switching just added stress and made it impossible to focus. We haven't tried switching that aggressively since then (although we've been considering it lately, as the circumstances seem better for it--that's why it's on my mind right now). On the other hand, it's still rare for us to switch less than once a day, and that's been absolutely great.
