Is it just me, or is the term "Black Bloc" to symbolize the violent Oakland anarchist faction of the OWS Oakland a racist term?!
Occupy Oakland General Assembly Fails To Establish Consensus On Non-violence Policy
The biggest complaint was lack of clarity of the language. Proponants of the inclusion of black bloc and violent tactics were unhappy because of the constraints it attempted to place and many nonvioloence proponants were unhappy because it wouldn't effectively prohibit violence/vandalism, and the language might be interpreted as legitimizing black bloc tactics. ...Just before the main nonviolence proposal was to be presented, it was withdrawn. Apparently the decision to withdraw the proposal resulted from intensive discussion between proposers, unions, grassroots groups, etc. The reason given was that at the current juncture (i.e. an implicit reference to the impending police raid, etc.), solidarity was perceived as more important than a discussion on nonviolence.
Theatre of the absurd.
Now, don't be letting the liberalism infect your thinking; long before the black bloc, there were Black Russians, Black Irish, Black Holes and black-balling.
So, the decision was to aim for "solidarity" rather than to expound and uphold some sound principles which means, as usually happens, the more leftist elements won.