I've been listening to the TDD guys for some while, and I think they may be on to something that's lot more important than just writing code. They describe TDD

I've been listening to the TDD guys for some while, and I think they may be on to something that's lot more important than just writing code. They describe TDD as "double entry bookkeeping". That is, you enter things in twice and then you always have a cross-check to make sure you prevent errors. The same theory is in action in most modern commercial airline cockpits: one person could fly the plane alone, but there's a purposeful redundency built into the system -- a cross check. Same goes for flight control hardware: one system is never enough. I'm sold. I want everything I own, from the metal on up, to consist of competing and cross-checking systems, ideally open source from different groups. So to answer your question, yes. All of it. It's got to be baked in everywhere. Sketching this out on the back of a napkin somewhere would be a hoot.