Don't it always seem to go that you don't know what you've got til it's gone? White Christians have a complex relationship with their pastors. While they love their pastor, they have (ideally) a full hour every week to observe and analyze every move he makes. All this combined with the white Christian like of gossip lead to a very interesting give-and-take.
This complicated relationship is only brought into clearer focus when the pastor is away. While the guest pastor occupies the pulpit, white Christians can observe this non-indigenous species that has wandered into their ecosystem.
Their regular pastor has a unique set of pastoral idiosyncrasies, familiar gestures and phrases, and verbal crutches that go completely unnoticed until a guest pastor comes to town. Suddenly, the congregation yearns for the previously intolerable "ums, "ahhs," and "you knows." In fact, there's a good percentage of the white Christian congregation that will use the guest pastor week as an opportunity to skip church. "After all," reasons the well-rested sleeping in white Christian, "If the pastor's taking a week away from church, then so can I."
Actually, come to think of it, white Christians don't really like guest pastors, but they DO enjoy how much guest pastors make them appreciate their current pastor.