Teaching professionals will tell you that the mastery of any material that you are trying to share comes when you actual do the teaching. You can know plenty about a given subject, you can develop lesson plans and prepare diligently, but until you actually teach the subject matter itself you have not mastered it.
This principle applies to leading in Christian community as well. If you want to have a greater impact in the world in Christian community you have to lead. For this reason we keep our leadership team small (5 people) and rotate individuals through the team frequently (about every six months). This relay leadership model keeps our leaders fresh, broadens the depth of our community, and safeguards against extensive hierarchy in organization.