What you describe is possible, but I'd be surprised if the size of core committer groups was that stable as project size grows. Intuitively, I'd expect the size

What you describe is possible, but I'd be surprised if the size of core committer groups was that stable as project size grows. Intuitively, I'd expect the size of the core committer group to grow more or less at the rate of the total active committer pool. At any rate, this can be tested quite easily, given an appropriate definition of what a "core committer" is... I released the dataset precisely to make it possible for other people to check this type of conjecture.