Why would this HighlighterActor method return too early?

gistfile1.js

/**
 * Why would "node-highlight" be emitted before showBoxModel() is called.
 * 
 * From logging I can clearly see initInspector > "node-highlight" > showBoxModel
 **/

highlightNodeFront: function(nodeFront, options={}) {
    let deferred = promise.defer();
...
    this.toolbox.initInspector().then(() => {
      this.toolbox.highlighter.showBoxModel(nodeFront, options).then(() => {
        this.toolbox.emit("node-highlight", nodeFront);
        deferred.resolve(nodeFront);
      });
    });
...
    return deferred.promise;
  },