Interesting article by Ben Horowitz:
Shared command always seems really attractive to the people at the top of the organization like the CEO and the board: “we have two world-class people, this gives us the best of both worlds! We shouldn’t get caught up in the conventions of years past. We’re all adults. We can get along.” It looks much less attractive to those who do all the work in the organization. To them it looks more like frustration, chaos, and delay.
From http://bhorowitz.com/2013/07/03/shared-command/
You have to have one person who will be ultimately responsible for any given decision in the company. And you have to make sure that final decisions are, well, final. Not final-until-someone-else-disagrees-with-you. I definitely agree that taking no decision is much worse than a bad decision made fast. You cannot course-correct unless you have set a direction.