The optimal innovation hypothesis (OIH) offers a good aesthetic and cognitive reference for the kind of linguistic creativity where minimal variations can have a strong effect on the audience and realize an overall intended goal. The same approach can be the basis for creative systems. The question is how to concretely evaluate not only their quality, but also their pragmatic effect. This paper describes the original evaluations of two systems based on the OIH, one automatically yielding witty headlines for incoming news, the other producing song parodies, varying the song lyrics to evoke a given concept. The goal is to bring attention to the importance of evaluating the pragmatic potential of creative systems, in addition to the quality of their output, and to demonstrate how such evaluations can be done.