Peer-assisted learning (PAL) strategies, such as the reciprocal style of teaching, have been shown to be effective in developing motor skills. Despite this research, little is currently understood of how PAL strategies influence the teaching-learning process. The purpose of this study was to use a didactic methodology (Amade-Escot, 2005) to examine the content taught and learned by two pairs of undergraduate students participating in reciprocal style (Mosston & Ashworth, 2002) episodes of indoor climbing. The didactic protocol included collecting data regarding student intentions, actions and interpretations of content, and the identification of problematic episodes in the teaching-learning process or Critical Didactic Incidents. The participants' improved their knowledge and performance of lower complexity climbing skills. Participants' failure to construct more sophisticated climbing content was as a result of deficiencies in the peer observer's in-task error diagnosis feedback and teaching style imposed constraints on teacher intervention. (Contains 1 table and 2 figures.)