There are the pushing-the-edge-of-excellence folks, constantly refining methods and approaches, who tend to be passionate about the holistic benefits of testing.
And there are the folks who write convoluted tests that, when you dig into them, just confirm that String's .equals() works OK. DAO/database tests which have mocking going on to the point where you're faking a database response of "hello", say, and then checking "expected response == hello". Then yay our test passes!!
Personally I feel our energy should somehow be spent collectively on getting the latter group to just not write total garbage, and that the bar for "good enough" is really not that high, after which we get into diminishing-returns territory. And I think, personally, that mocking is responsible for so much confusion in folks that ultimately don't really know what they're trying to accomplish.