I actually feel the exact opposite way when it comes to successful tests like the present one. Namely, these tests often also rule out modified theories of gravity which, to me, suggests that, by often considering more or less random (read: ugly) and little-justified modifications of general relativity, these theories have been looking in the wrong place when it comes to explaining dark matter (and, possibly, dark energy). …which, for me, not only makes the mystery of dark matter all the greater but also makes me appreciate Einstein's beautiful theory even more. :)