[jstultz]

Perhaps I'm missing something, but it seems like what this post describes isn't so much "test driven development" as "testing". Rigor of the data analysis aside, unless I misread, it seems like a comparison between not testing at all, and testing (I didn't notice any specific mention of TDD methodologies).

Shouldn't the comparison be between full-on TDD (e.g. write tests first, etc etc) and 'old fashioned' testing (for lack of a better term)?

[jphpsf]

You are absolutely right. On one side, the UI is using automated tests (using TDD) and on the other side there is no tests (backend server has no tests and first 2 years of the UI had not tests).