Nar-Anon recommends the group conscience process to reach consensus within a group,, an area, a region, and in world service committees. At the world service conference (WSC), however, that process is dropped. The WSC uses the system of representative voting. A majority wins in a vote, even if it is a slim majority.
I cannot speak for other twelve-step programs, but I think they probably do similarly.
Is this because we do not trust the process?
Do we not trust that Higher Power will lead us to the right conclusions?
Do we not have patience to wait for consensus?
I believe there are factions of the Society of Friends (Quakers) who still use the group conscience when making decisions at all levels of the organization - even when making decisions at the world level. The process works. It might not be as fast as we want. It might not allow us to get the results we want. But consensus through a group conscience will result in the best, most informed decision.