You might be able to get 10% more raw code out of peopletemporarily at the cost of having them burn out 100% in a year. Not a big gain, and it's a bit like eating your seed corn.

You might be able to get 20% more raw code out of people by begging everybody to work super hard, no matter how tired they get. Boom, debugging time doubles. An idiotic move that backfires in a splendidly karmic way.

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).

In my recent stint at a medical con biz, we were distracted by everyone's phone calls (frequent), watercooler chatter, the sales dude shmoozing, sales and CEO showing off the veal-farm to prospective clients and other tourists... I survived with headphones, but I think it pissed off the sales dude. He'll learn when his contracts can't be fullfilled.