>The other trouble is that it’s so easy to get knocked out of the zone. Noise, phone calls, going out for lunch, having to drive 5 minutes to Starbucks for coffee, and interruptions by coworkers — especially interruptions by coworkers — all knock you out of the zone. If a coworker asks you a question, causing a 1 minute interruption, but this knocks you out of the zone badly enough that it takes you half an hour to get productive again, your overall productivity is in serious trouble. If you’re in a noisy bullpen environment like the type that caffeinated dotcoms love to create, with marketing guys screaming on the phone next to programmers, your productivity will plunge as knowledge workers get interrupted time after time and never get into the zone.
https://www.joelonsoftware.com/2000/08/09/the-joel-test-12-s...
Others have known since the 60s or 70s - it's touched upon in Brooks' 1975 The Mythical Man Month
But it's NOT because of the mythical "10x programmer" (another Spolskyism)
It's because of communication overhead - in general, the smaller the team, the faster the solution
