I've seen TDD used in the same way "teaching the test" is used. They say, "We've got 100% coverage! Our quality is high!" Meanwhile people are bitching left and right on Twitter about the product and there are deeper more endemic problems. It's just another form of scientism gone bad.

It has it's merits, but has it's negatives too. Blindly pretending there are only positives is disingenuous and a hallmark of scientism. I think that's all DHH was saying.