Is it possible to put a large team to dig at 20 places 20 feet each and get water when we know that you need to dig 100 feet to get the water?
Do you think, nine ladies together can nurse a baby in one month instead of nine?
Bigger the team less the productivity. Amazon has two pizza rule – with focus on efficiency and scalability, it helps establish better coordination, learning, and ramp up time.
The advocacy for a large team is cited when the project is large. In such cases, it makes sense to have multiple teams based on milestones and then join them at a specific point.
While executing 100s of projects, I have experienced that having a larger team makes it slower wasting lots of time in learning and coordination.