> Unfortunately most software is just not well defined up front. This is true, and I think that's why TDD is a valuable exercise to disambiguate requirements.

> Unfortunately most software is just not well defined up front. This is true, and I think that's why TDD is a valuable exercise to disambiguate requirements. You don't need to take an all/nothing approach. Even if you clarify 15-20% of the requirements enough to write tests before code, that's a great place to begin iterating on the murky 80%.