[Jtsummers]

What do you question about it? The point of the specific essay was that the work of development/engineering cannot be sped up linearly by adding people. You still see this attitude with managers today: The team of 5 is running behind, let's put that other team on the same project, now it's 10 people. But those 5 new people:

1. Don't know the code base or problem domain. So they'll spend months getting up to speed.

2. Will increase the communication overhead (now each person has to coordinate with up to 9 others, not just 4).

On the small scale of this example, you may see good results. 5 more people isn't a huge amount of communication overhead, and if they're experienced (perhaps even formerly worked on the same or similar project) then you'll see an immediate drop in productivity and then a quick rise back to the new baseline. But will that hold with another 10 people? 20 more beyond that? Each doubling will not continue to halve the time to develop the project, there are limits, and at some point the returns will be negative. The additional people will slow it down. Not just the initial slow-down, but also the new baseline after things settle will be lower than before adding them.