[chrisbennet]

Joel Spolsky writes of this in his essay "The Joel Test: 12 Steps to Better Code"

http://www.joelonsoftware.com/articles/fog0000000043.html

See #8 "Do programmers have quiet working conditions?"

"Here's the simple algebra. Let's say (as the evidence seems to suggest) that if we interrupt a programmer, even for a minute, we're really blowing away 15 minutes of productivity. For this example, lets put two programmers, Jeff and Mutt, in open cubicles next to each other in a standard Dilbert veal-fattening farm. Mutt can't remember the name of the Unicode version of the strcpy function. He could look it up, which takes 30 seconds, or he could ask Jeff, which takes 15 seconds. Since he's sitting right next to Jeff, he asks Jeff. Jeff gets distracted and loses 15 minutes of productivity (to save Mutt 15 seconds)."