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)?
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)?