story observer

The "story observer" role is something new to me--maybe only exists in my current team--but anyway, at least once a day this person walks around the room to remind pairs to consider whether they're blocked, ensures they're clear about the goal of the end-user, and asks whether they're still in scope of the story card. This observer, I suspect, is not necessary in a gelled/disciplined team, but in the early stages of forming, I think it can be helpful.