Are measurement theories falsifiable, and should we care?

Some measurement theories, of which classical test theory (CTT) is a prominent example, depend on definitions rather than on real assumptions that are susceptible to empirical confirmation or disconfirmation. Thus, there is a falsifiability issue that can be, and has been, used as a criticism. I suggest that this issue be replaced with that of surprising implications. As an example, although I agree that CTT is not falsifiable, it does suggest surprising implications. Consequently, CTT is a worthy theory despite not being falsifiable. I argue, more generally, that surprising implications are more important for evaluating theories than is their falsifiability.