Continuing vocational training benefits from the employees' ability to share individual experience and expertise with their co-workers, as these assets constitute competitive advantages for companies. IT-supported systems can facilitate processes of knowledge elicitation (e. g. as part of collaborative co-creation) to ensure retainment of preferred qualitative characteristics of the resulting knowledge artifacts and provide ample opportunities to manage and configure a growing number of such artifacts in a company's repository. It remains unclear however, how such collaborative and digital co-creation processes can benefit the individual co-creators' expertise development. To address this gap in research and practice, an IT-supported co-creation system for microlearnings is designed and evaluated with master craftsman trainees of an inter-company vocational training center. With the deployment of the co-creation system, knowledge elaboration was examined via a qualitative evaluation of concept maps. By applying categories of the maps' semantic properties and comparing features of expert knowledge derived from expertise research and concept mapping literature, we evaluate the process' function to support expert knowledge elaboration as a desirable learning outcome for co-creators of shared digital artifacts. Analysis of the concept maps shows an absence of theoretical reasoning and an emphasis on contextual factors with minute details of work processes, indicating more practical than expert knowledge formation when co-creating shared digital artifacts. To improve the IT system's effective support for expert knowledge elicitation, adjustments to the structured procedure are discussed and future research directions and limitations of this study are addressed.