anchor.diff:  
       // Toggle children on click.
       function toggle(d) {
  -      // if (d3.event.defaultPrevented) return; // ignore drag
  -      if (d.name == 'view!') {
  -        viewPlan(d);
  +      if (d.view_node == true) {
  +        d3.event.defaultPrevented;
  +        return;
         }
         if (d.children) {
           d._children = d.children;
  
positive.code: 
        // Restart the force layout.
        force
            .nodes(nodes)
                    .linkDistance(200)
          .charge(-670)
          .gravity(.05)
  
                // .distance(100)
                // .charge(-670)
            .links(links)
            .start();
  
        // Update nodes.
        node = node.data(nodes, function(d) { return d.id; });
  
negative.code:       update();
      }
  
      // Returns a list of all nodes under the root.
      function flatten(root) {
        var nodes = [], i = 0;
  