I understand you better. Indeed, I notice that to most programmers, the mocks stand out more than other aspects of the test, so they easily see the mocks as their targets to remove in a test. I see mocks (expectations, specifically) as just another kind of assertion, and so I try merely to look for "un"cohesive groups of assertions as a signal to split tests apart, and eventually to split modules apart. Irrelevant details in the test tend to act as a unifying signal: fewer of them correlates highly with "better" design.