An excerpt from People Management:

“…he quickly noted two distinct groups of employees: data sets showed one would consistently relax at tables of four people, even when the make-up of the table varied from day to day. The other group consistently had 12 people.

Analysis confirmed that the people in larger groups were much more productive. This was because they were talking to people in different parts of the company, giving them a broader view of what was going on in the rest of the business and how they fitted in.”

“We saw that near one door all the tables had four seats and near the other, all the tables were larger, with 12 seats. People were just sitting at the same tables,” says Waber. “If you’d gone to the senior team and said ‘have you thought about how big your tables are…?’ they would have thought you were crazy.”

Source: Churchard, C. (2013) We Love Data. People Management. September 2013, pp.20-24.