…because the human brain needs time to shift gears between tasks, the more switching back and forth you have to do — between, say, talking on the phone, reading e-mail, and thinking about your next meeting, all while scarfing down a sandwich at your desk — the less proficiently you will tackle any of it (except maybe the sandwich).
The “time cost” of refocusing your attention may be only a few seconds with each switch, but the researchers found that, over time, it reduced people’s total efficiency by 20% to 40%.
The author then writes:
So it could well be that, in the era of knowledge work, the most prosperous companies will turn out to be those that encourage people to build some slack into their days.
That will never happen; there’s no way to determine if the “think time” helps productivity.
This is all old news anyway for those in the IT industry.