[supersan]

Up until now it has mostly been opinions and biases and even though many popular programmers[1] have been saying this for a very long time, it's great to see a controlled study done about it.

This makes it a fact and a great counter argument for helping a lot of programmers who are being forced to practice TDD because of the generally accepted claims in productivity and code quality associated with doing it.

[1] http://david.heinemeierhansson.com/2014/tdd-is-dead-long-liv...

[girvo]

Keep in mind though, that the study shows that it's no better than testing after iterative development. Testing is still required, and I'd wager that the study participants following the ITL process didn't have external business pressure to skip the "test-later" bit...