anchor.diff:      
       save @local
   
  -    if @local.dragging
  +    if hist.dragging
         @selectOpinions ev
   
     render : ->
  
positive.code: #      The base size of the avatars, as determined by the physics 
  #      simulation. This piece of state would be local, but it needs
  #      to be settable from the physics simulation.
  #
  # local state: 
  #   click_will_defocus
  
negative.code:       selected_opinions = @getOpinionsInCurrentFocus()
  
      # Deselect if we've reclicked on same selection
      if !hist.dragging && 
          !@local.last_selection_via_drag && 
          (JSON.stringify(hist.selected_opinions) == JSON.stringify(selected_opinions) || 
            selected_opinions.length == 0)
  