Just as WAC pedagogy and writing studies both stress the ways that writing and communication practices can act as both heuristics and products of genre-based, discipline- specific knowledge, in much the same way, performance, too, can be used as a heuristic and as a product and should be more fully explored in WAC theory and pedagogy. This article argues for a theory of performance across the disciplines based on performance theory, specifically, how Richard Schechner's concept of the rehearsal or "twice behaved behavior" can be used as a heuristic to promote communication and thinking about writing assignments because of performance's direct relationship to audience, and similarly, how Ric Allsopp and Carol Bergval's concept of "performance writing" reconceives notions of rhetorical delivery that can be used in discipline-specific courses. Two case studies are examined for the ways in which they demonstrate performances which focus identification and division with the audiences across the disciplines.