Brilliant.

Indeed, I have found that for building cloud software, small teams of 5-6 people are not the most effective. The reason is people have to do too many different things. The most effective team I have seen building cloud software had about 14 people.

Also, I agree that Dunbar's number is irrelevant. In a team, one rarely communicates frequently with most people. It is more common to communicate with only a few in the span of a few weeks.