This chapter presents an interdisciplinary research study, a comparison of ice hockey coaches and orchestral conductors. It explores mental preparedness in expert performance, the process and results of preparation for competition and concert as its object. The study had its successes, notably the transfer of qualitative aesthetic modes of assessment from music to sport and the adaptation of quantitative social science models to the study of musical performance. The chapter examines these gestural economies in light of five theoretical frameworks: semiotics, politics, style, aesthetics and the psychological nature of expert performance, in particular the evidence of expert practice and of pathology. The general rubric under which the chapter operates is the burgeoning field of performance theory, a field in which our human kinetics colleagues have anticipated in many regards.