Constitutional pluralism has become a principal model for understanding the legal and political structure of the European Union. Yet its variants are highly diverse, ranging from moderate “institutional” forms, closer to constitutionalist thinking, to “radical” ones which renounce a common framework to connect the different layers of law at play. Neil MacCormick, whose work was key for the rise of constitutional pluralism, shifted his approach from radical to institutional pluralism over time. This paper reconstructs the reasons for this shift—mainly concerns about political stability that also underlie many others' skepticism vis-à-vis radical pluralist ideas. It then seeks to show why such concerns are likely overdrawn. In the fluid, contested space of postnational politics, a common, overarching frame is problematic as it might inflame, rather than tame, tensions. Leaving fundamental issues open along radical pluralist lines may help to work around points of highly charged contestation and provide opportunities for resistance from less powerful actors.