I grant you that linting catches bugs, but what I've argued for (perhaps badly) is that the bugs it catches are very shallow, but more importantly they make up

I grant you that linting catches bugs, but what I've argued for (perhaps badly) is that the bugs it catches are very shallow, but more importantly they make up a relatively small subset of the bugs proper unit tests catch. That's what makes the comparison you made deceptive. I use both linting (pylint actually) and unit tests, so I am not advocating that you should scrap your linting tools. I am just trying to point out the difference. Your B) argument is yet another indication that the tests are not good enough. The example bug OP posted is what made me comment in the first place. If your tests don't catch that your tests are useless.