I think that what you say makes a lot of sense and I completely agree with doing code-test-code. True TDD (which I have tried) requires too much constant change

I think that what you say makes a lot of sense and I completely agree with doing code-test-code. True TDD (which I have tried) requires too much constant change to be practical. The churn I was referring to though is less that of short-term interface changes but more to do with long-term multi-month revamping of the product proposition. During these highly exploratory phases, the main risk with errors is not that they multiply but that they never happen because the code isn't run. I always knew this in theory but like all lessons I needed to learn it the hard way to really appreciate.