Scalability of software product teams

I'm curious that with all the software development practices being flung around these days whether nay though has been given to how to scale up software development.,

I've often heard it said that small teams are better than large teams but what happens when you have a large application or perhaps a large suite of applications that are all supposed to work together. How do you scale up development in such a way that you don't end up programming resources.

Fred Brooks says that a large programming teams won't as well as a small programming team. The thing is, in some sense, every day programmer work on huge projects even if all they do is write a small, 100 line python program. That python script will use python (a large project) which relies on an operating system (a large project) made up of large components etc... We are always leveraging someone else's code on someone else's project.

writing library of framework code is much harder than writing application code. The trick is how much more effort does it take? ..especially if the library is only being used in house? How big should development teams get before the project is split into two groups or three? If we say that teams should be of about 5 people, how many teams should we have before we should create a team responsible for tracking down and eliminating duplicate code - by turning it into an inter-team library?

I haven't seem anything that attempts to tackle this.

There's another question.

Java's API and python's API both have really nice documentation. I would expect that any teams that try an work together would need at least this amount of documentation. Do they need anything else? I mean python's API and Java's documentation are all I use.

If joint design is being done, that is an interface is being negotiated, which is the best way of doing this? Sure, if you on have 2 teams negotiating a handful of interfaces this probably isn't a problem but what if you have 3? 4? 5? 10? 50? If a project is made up of many teams is it a good idea to have a meta-team responsible for maintaining the large project's design integrity?

I don't know. I haven't seen anything written about this. It's important, though. Many software projects are huge and right now most best practices are optimized for smaller teams and small software projects. Imagine trying to to native agile program with 50 teams of 5. You're project would be a mess.

..now what?