Here's an example. I've always taken it as a given that orthongonality is highly desirable. But on page 2 of the interview, Matz describes how orthogonality can be bad.

An example of orthogonality is allowing any combination of small features or syntax. For example, C++ supports both default parameter values for functions and overloading of function names based on parameters. Both are good features to have in a language, but because they are orthogonal, you can apply both at the same time. The compiler knows how to apply both at the same time. If it's ambiguous, the compiler will flag an error. But if I look at the code, I need to apply the rule with my brain too. I need to guess how the compiler works. If I'm right, and I'm smart enough, it's no problem. But if I'm not smart enough, and I'm really not, it causes confusion. The result will be unexpected for an ordinary person. This is an example of how orthogonality is bad.

The orthogonal features, when combined, can explode into complexity.

Interestingly enough, Ara posted some lessons that he's learned on XDoclet. And a sizable portion of his post involves this idea. He's talking about accepting people too quickly, and then having them leave, etc.

Here's a link to the joining script presentation from the symposium.

The various open source foundations work in different ways. I'll talk about the Apache Software Foundation, since I know the most about it. The ASF exists to provide resources to its projects, which includes obvious stuff like servers and bandwidth. We also have a legal defense fund (should we ever need it), and the members of the Foundation also benefit from legal protection in the event of legal action against the foundation. That legal protection, and the value of the Apache brand, are two of the biggest reasons that projects should be interested in becoming ASF projects.

I think that the various foundations need to start acting more like non-profits that sponsor scientific research, and provide the kind of legal, IP, and financial support that is necessary for open source development to flourish. That's in addition to servers and bandwidth. Today in the OSAF Chandler IRC, the OSAF folks announced that they have received a $2.75M grant from the Mellon Foundation. I expect that the Mozilla Foundation may start to pursue this sort of funding.

The papers from the HBS/Sloan workshop can be obtained via this page.