The Jan-Feb 2011 issue of Harvard Business Review had an inset that resonates in my environment.
The optimal size of a decision-making group is 7. Deduct 10% effectiveness for each additional person. If you have more than 17 in your group, you are lucky if any decisions get made.
In LMD we are lucky since the true-decision making group is small and strong leaders guide us along. In my real life, not so good, but new additions and necessity are turning the tide on effectiveness.