The real problem here is that all the mocking is noisy and changes the thing we're testing. I'd rather have standard test data that we can slot into the configs and assertions as necessary, which limits the noise somewhat and still alerts us if we're depending on behaviour in some other unit that has changed.

Lots of mocking indicates that we're too tightly coupled. If we *need* to be tightly coupled, mocking out all the deps means we're not testing the interactions between them. If we don't need to be tightly coupled, we should refactor.