Owing to its density and complexity, the traditional Roman liturgy—and the same, of course, would be true of any traditional liturgy—gives rise to multiple “hierarchies” of participation, which I will call here “ecclesiastical, sanctuarial, and congregational.” What I have noticed is that a complex and subtle gradation is of the essence of the rite, although it is sometimes occluded either by a simplified performance of it or by demographic circumstances (for example, Mass in a…