In my experience, on projects with often-run automated unit test suites with good coverage, development goes faster. Part of this might be because for code to be highly testable, it usually also has to be well-designed and architecturally sound.
I agree. When interviewing I can usually weed out those who write tests (and write good tests) from those who just claim they do.
How?
People who don't really write tests will tell me that the advantage of unit testing is being able to see when code changes have broken stuff (which is fair enough and true).
Those who regularly write unit tests will probably bring this up- but often their first point will be 'It helps to structure code properly, make me think about dependencies, modularise code appropriately'
