In Martin Fowler's blog he talks about how Wikipedia's controls differ from a completely "open" wiki
The interesting part is a nice summary of Agile's approach to control in its environment:
Much of the agile software movement is about loosening controls, shifting more to asking forgiveness rather than permission. Yet loosening controls isn't the same as anarchy and no control - a misrepresentation that's commonly thrown at agilists too. It's about asking how we can use a minimum of controls, so that that we don't suffocate the good in our desire to protect ourselves from the bad.
As we deploy engineering tools, there's an unnecessary desire to jump on available mechanisms for restrictive control, rather than deploying the utility of the tool and using its auditing capabilities to deal with problems as appropriate.
I'm finding tools to be most effective when the login is only required so you know who's doing what, not to enforce permissions and restrictions on what people can do. The latter is a management crutch for dysfunctional groups.