Perhaps an example of such tweaking is the "discovery" of black holes reported to the public, when the definition of a black hole precludes definitively observing them. What actually happens is that astronomers plug values for observations above a suspected black hole (e.g. the orbital speed of stars) into Einstein's theory of gravity, and let the theory tell them whether they "discovered" a black hole. Then they let the media report the black hole as a confirmation of Einstein's theory.