Oh, and one more thing, he developed his "Art of Unix Programming" book in a Cathederal style and then released it under a non-OpenSource license.  (he used the most restrictive Creative Commons license (Attribution required, derivative works forbidden) plus some additional restrictions which he wrote himself.

But, I don't feel like spending too long adding criticisms to a wikipedia page, so I sketched down my ideas here in case someone else wants to build on them or whatever.