I appreciate the thoroughness of your comment. I also agree with some of what you said. For me, TDD is not so much about testing the code as it is about effectively writing the code. The only point that you brought up that I would like to make a counter argument to is the idea that you should get the design right on the first try. I don't agree that it is a good idea to design the system thoroughly up front. For me, using unit test to allow me to refactor throughout a project is very useful and allows me to become better at design everyday. It's an excellent way to prefect your skills as a code designer. It also leads to a code base that can be explained without any "well it used to..." sort of talk.

But again, I emphasis that I found everything else that you brought up to be perfectly valid.