View rendering twice? (or rather, nested routes are reloading data?)

Hi! I have two routes called classyears and classyear. They’re nested like o:

this.resource('classyears', function(){
    this.resource('classyear', { path: '/classyear/:classyear_id'});
});

Posterkiosk.ClassyearsRoute = Ember.Route.extend({
  model: function() {
    return Posterkiosk.Classyear.find();
  }
});

Posterkiosk.ClassyearRoute = Ember.Route.extend({
  model: function(model) {
    return Posterkiosk.Classyear.find(model.classyear_id);
  }
});

I’m using the Ember-model RESTAdapter. When I load /classyears/classyear/:classyear_id, it looks like classyear is rendering its data twice. Once with the correctly-loaded data, and once with no data loaded. The order appears to be random. If the no-data option happens last, it wipes out the correctly-loaded data, leaving a blank page.

Any thoughts?