Dale Emery does a nice job of highlighting the assumptions around why we multi-task. And then he shows that those assumptions are misguided. Here is the highlight from Multitasking and Conflict
... This explains how multitasking can remain so popular even though everybody knows it slows the work. The real purpose of multitasking is not to finish work faster. The real purpose of multitasking is to avoid conflict.
And that's a tragedy, because multitasking does a lousy job of avoiding conflict. ...
So, to assuage a fear that may not even exist, I tend to multi-task? How embarrassing. Sometimes it seems so much easier to do that than to actually think about what is important and the needs of people involved.
Dale continues with the recommendation that people need to improve their negotiating skills when taking commitments and improve skills in resolving conflicts that come up anyway. We can't know there will be a conflict until we ask -- don't just assume the conflict exists. Part of doing a good job is understanding the needs of the people to whom you've committed, whether it is running a workshop, writing the best software ever, or changing diapers.