Is multitasking unethical?

In a recent column at Business Week, Bruce Weinstein (aka “The Ethics Guy”) argues that multitasking is unethical. He writes of his own technologically assisted slide into doing too many tasks at once:

I noticed that the more things I could do with ease on my computer, the harder it was to focus on any one activity. My natural inclination to jump from one thing to another prematurely was now aided and abetted by technology–the very thing that was supposed to be helping me. Then, after the PDA and cell phone became a part of my daily life, I found myself, like millions of others, faced with even more interruptions, and it became increasingly difficult to concentrate. The technological advances that once seemed so liberating had become oppressive.
I came to realize that multitasking isn’t something to be proud of. In fact, it’s unethical, and good managers won’t do it themselves and will not require it of those they manage.
Here’s why multitasking is unethical.
When you multitask, you’re doing a lot of work, but you’re not doing most (or any) of it well. A new study published in the Proceedings of the National Academy of Sciences revealed that people who fired off e-mails while talking on the phone and watching YouTube videos did each activity less well than those who focused on one thing at a time. Psychiatrist Edward M. Hallowell, author of CrazyBusy: Overstretched, Overbooked, and About to Snap! (Ballantine, 2006), puts it this way: “Multitasking is shifting focus from one task to another in rapid succession. It gives the illusion that we’re simultaneously tasking, but we’re really not. It’s like playing tennis with three balls.”

Weinstein’s column notes a variety of multitasking that research keeps showing to be a significant danger to our physical well-being, drivers texting, emailing, or talking on cell phones while operating their cars, trucks, trains, or other heavy equipment. In these cases, it seems pretty clear that divided attention has an ethical cost given the harm it can inflict to the multitasker and those around her. But Weinstein’s claim extends to other, non-lethal, sorts of multitasking. Moreover, he claims that managers have a special duty not to demand multitasking from those they are managing:

Since multitasking interferes with the ability to do one’s job well, the good manager sets an example by focusing on one task at a time. You can’t expect the people you lead to resist the urge to multitask if you can’t do so yourself.

He follows this with advice that I find completely reasonable and humane about letting your underlings (and yourself) unplug from the internet, the PDA, and the phone during their own time (indeed, recognizing that a good chunk of their time every day is their own time, not the organizations), letting people stay home when they’re sick, letting them take a vacation from work (even the emails) when they’re on vacation, and discouraging work-driven dived attention when driving.
But I’m not sure I fully agree with Weinstein’s strong claim that multitasking is itself unethical.
I’m inclined to think that the ethical status of multitasking may depend on a bunch of considerations:

• Is the person multitasking competent to execute the multiple tasks being undertaken in the same time interval (i.e., the quality of each of the tasks, once completed, will meet the necessary standard)?
• Does undertaking these tasks simultaneously increase the likelihood of harm (whether to the multitasker or to someone else)?
• Does undertaking these tasks simultaneously increase the stress level of the person performing them relative to undertaking them sequentially?
• Does undertaking these tasks simultaneously increase the likelihood that the tasks will actually be completed (or completed in a timely fashion) relative to undertaking them sequentially?
• Does the person undertaking these tasks have the freedom to decide whether to perform them sequentially or simultaneously?

Actually, some of these considerations are clearly connected to each other — whether you can decide how to manage the tasks you are charged with completing can certainly have an effect on your stress level, and an increase in your stress level can obviously be a harm worth taking into consideration.
The main point, however, is that there may be some tasks that it is perfectly possible to combine without doing a worse job than you would doing them one by one. Decreeing that multitasking in such a case would be unethical doesn’t make sense to me, at least not in the case where such multitasking doesn’t produce some other harm to someone.
My own experience is that certain kinds of multitasking are not only doable, but downright necessary. Dinner would not get to the table most nights if I could not simultaneously manage something roasting in the oven and something else simmering on the stovetop while cleaning and preparing components of a salad. I can sort and fold socks while reading spelling words for a sprog’s practice test and both jobs get done well. And I’d still be in grad school doing the work for my chemistry dissertation if I hadn’t been able to monitor my experiments while reading the literature, grading student papers, writing exams, or preparing solutions for the next round of experiments.
None of this to say is that there aren’t tasks which are best done with one’s full attention and without interruption. Calibrating pump flow rates before my experimental runs was one such task, and that’s exactly why I used to get to the lab by 5:30 AM, to get it done before the phone in the lab started ringing. (I managed, however, to perform these calibrations with the radio tuned to NPR.)
The point, though, is to be able to recognize what conditions are necessary to do a good job with a given task. Then, discharging your obligation to do that task well involves creating (as much as is possible) those conditions. A given person may need to bring different levels of focus to different tasks — meaning some of them are fine to perform simultaneously and others are not. A given task may require differing levels of focus from different people trying to perform it — meaning that some people may be fine taking on this task simultaneously with others while other people have no reasonable chance of multitasking it successfully. A given task may be more easily combined with some tasks rather than others. And, arguably, some of the tasks we take on may bring very mild consequences if we screw them up — so much so that we’d be inclined not to grant those consequences any ethical weight. (What’s the worst that happens if, while I’m mentally mapping out a lecture, I manage to put my T-shirt on backwards?)
I do agree with Weinstein that one ought to err on the side of not multitasking when one is operating heavy machinery or engaging in other activities with the potential to do serious harm to oneself or others. Moreover, I suspect that people are not always great at gauging their own ability to multitask successfully; if we’re going to multitask, then, we have a responsibility to seek out accurate information about our competence in combining the tasks we intend to combine. And, I think it’s unfair to demand that people multitask in instances where they can’t do it well and when they can do each of the tasks well when taken one at a time.
Still, unless we can establish that multitasking never works, or that it always puts someone at risk of a significant harm, I’m not ready to endorse the blanket claim that multitasking is unethical.
(Of course, I was doing other things while I thought about my objections to Weinstein’s claim, so it’s possible I’ve overlooked something.)