The main thread is just the hub that connects the stories...players were supposed to pair off into smaller groups and create other threads when they got into their own stories.  Example.  John, Jessica and Alice have their characters meet in a seperate area outside one of the main hub towns.  John and Alice are Alliance, Jessica is a horde.  Conflict ensues.  To insure they don't both other players they start a branch thread.   Entitled.  Fuel to the Fire: (Insert name)