def spawn_missing_workers_for(queues)
      worker_delta_for(queues).times do |nr|
        spawn_worker!(queues)
        sleep Resque::Pool.spawn_delay if Resque::Pool.spawn_delay
      end
    end
def spawn_missing_workers_for(queues)
      worker_delta_for(queues).times do |nr|
        spawn_worker!(queues)
        sleep Resque::Pool.spawn_delay if Resque::Pool.spawn_delay
      end
    end
}}}
 methods that operate on a single grouping of queues {{{
 perhaps this means a class is waiting to be extracted