It's not just about meaning of the words, it affects the reader's biases. Basically, it's countering one rhetorical tactic with another.
If the author had left out the first 8 or so paragraphs, this might have been worth reading and sharing. As it stands? I don't see why it's nearing the top of the front page.
If you dig through Bob's post, he does have a decent enough point - the purpose of tests is to feel confident about refactoring and deploying code, such that your development team can work quickly. I totally agree with that point. It's just a shame the point was buried.
and then goes on a rant that lasts half the blog post.
>To my knowledge no one seriously teaches abstinence only sex education.
... you have to wonder if the rest of the post can recover its credibility, or whether it will continue as an unreasoned rant.