I wrote concentrate not code. Socializing was more a term for mails, calls and meetings plus the sometimes very productive coffee machine talk.

I can code without concentration but did you ever measure your productivity and and error rate over time? For me 5h is a sweet spot after that error rate goes up and productivity goes down. If the errors are significant they could cost much more time later on. If the job isn’t that sensitive of course you don’t have to concentrate.