This is a really important set of discoveries about how we think. The recommendations also fly in the face of many a manager’s personal philosophies. When you, “must be able to manage multiple competing priorities”, then you will only succeed if you insist on serializing that workload as much as you can.
All Agile methodologies are designed to narrow down your workload, to let you stay in a focused, single topic “flow”. This article explains why focus is so important.
If you are disappointed with your productivity then you need to look at this closely. Most people are being affected by this. If you are being told to emulate a person who is supposed to be “great at multitasking” you may want to look at the kind of work they are doing and how well they are actually doing it.
My personal experience is that when my peers appear to get things done more quickly in an already fast paced environment, they are actually making tons of errors, covering or ignoring the effects, under-delivering, and over-claiming. Inevitably their work has to be redone or thrown out.
If you do large volumes of repetitious work then you might be able to be an exception to this rule, but only to a point. There are thousands of factory workers with missing fingers and huge workman’s comp claims because they were going so fast.
In the tech world, too fast is equivalent to sabotage.
For managers, here is the best ways I’ve seen for managing a huge backlog of projects. You should look into it – http://stackedsignal.com/wp/?p=136