That dratted Sitz im Leben thing again...

First, human activity is situational, which is to say that much of what is important to it cannot be grasped outside of the specific context in which it occurs. When abstracted from its immediate context, an activity is not quite the same activity. Practice may embody determinative influences deriving from other situations, but practice is not the mere expression or effect of these influences. Indeed, it can be said that a focus on the act itself renders these 'influences' (structures or sources) nonexistent except insofar as they exist within the act itself.— Ritual Theory, Ritual Practice, page 81