_updateCacheParams is not a function

I have a nest route for goals which is setup as such:

this.resource('clients', function() {
    this.route('new');
    this.route('client', { path: '/:id' }, function() {
      this.route('profile');
      this.route('sessions');
      this.route('payments');
      this.route('goals', function() {
        this.route('show', {path: '/:id' });
        this.route('new');
      });
      this.route('messages');
    });     
});

Going to the index route of Goals works fine where I have a defined goals.hbs and goals/index.hbs templates but only a goals.js controller. You can see this setup from the Ember inspector here:

The problems, however, show up if:

• I add a explicit goals/index.js controller rather than relying on the auto-generated one
• I navigate to the "clients.client.goals.new" or "clients.client.goals.show" routes.

In all cases the error is effectively the same. In order to be explicit, let's take the case where there is not a goals/index.js controller but I navigate to "clients.client.goals.new". In this case I get the following error:

Error while processing route: clients.client.goals.new controller._updateCacheParams is not a function TypeError: controller._updateCacheParams is not a function

Very odd, I'm doing nothing fancy here. Really don't understand why I'd get this error. Any help would be greatly appreciated.