I had a great affinity with this Chapter because I've seen a change of attitude and working at Church due to the change in this paradigm.
Viola's basic assumption is that leadership is effectively a function not an office. That most structures within the Church are hierarchical based. The results been, the Church community is overly reliant on one person to do most of the work.
Most of Viola's disagreement is how the Old Testament understanding of 'Priesthood' is carried into todays church. Where it was not seen in the New Testament. That the 'Preisthood of believers' should be the dominate force, in understanding leadership.
One area which I would disagree is his comparison of leadership in a 'Gentile' setting. I would argue especially if you read any modern day organizational leadership book. More than ever in history of leadership/management. There role more than ever is bringing together different skill sets in a facilitatory manner to reach certain objectives. Certainly this has been my experience in Nursing.