In our highly specialized society we don't usually think this way. I so often hear people saying things like, "I can't belived they asked me to do that -- it's a waste of my talent and training." Or "they are too busy to ask - I'm sure they will say no." I know that there are some folks that are trained to a specific skill level. I understand that it may not make sense to have someone who has a lot of training do a task that someone with no training can do. And I also understand the incredible value of stepping outside of our competence and into someone else's territory almost always gives us a better understanding of their contribution.
When a pastor decides to clean the toilets in the church maybe that's not always an indication of overfunctioning. It may also be a way to remember that everyone has to deal with unpleasant tasks and clean up messes not of their own making. When the person who has always been "the worker" is asked to lead a program we always learn something new about how we might function together. There is a level of humility that should be an appropriate part of our Christian life. A humility born of joy in being created one of God's lovely creatures.