Three partners, the city of Bobigny, Polimorph association and the MRTE laboratory of the University of Cergy-Pontoise-undertook in 2013/2014 the action-research project "Places of memory, places of urbanity" on the site of the former Bobigny railway station in the Paris region which served to deport one third of French Jews during the Second World War. The project was financed by the Ministry of Culture and Communication within the program "Intercultural practices in heritage institutions" and by the City of Bobigny. The purpose of the action-research project is to integrate the site better in its current territorial and social context, the idea being to transform the railway wasteland into a place of memory and a place of urban life for Bobigny. The action-research also sought to explore the process of patrimonialization by experimenting with participatory mechanisms. The initiative led to a situation of disagreement between the partners, to a progressive blockage and the breakdown. This article attempts to evidence beyond individual and collective emotions the underlying phenomena, facts and situations that led to the blocking of the transversal approach and to the interruption of actionresearch, such as mutant identities, divergent ideas of conflict management, ubiquitous sectorization and maintenance of dominant spokespersons. Furthermore it explicates how these may be recurrent in intercultural practice and how they are intrinsically related to the shaping our environment. It reflects on the role of the architect in transversal design process and how an alternative model than the juxtaposition of material and immaterial phenomena is necessary to bridge the gap between body and mind, individual realities and social realities, and to consider a continuity between sensing, imagining, telling and enacting upon our environment.