code: public function onModelLoad(Varien_Event_Observer $observer)
      {
          if (!$this->canCollect()) {
              return;
          }
  
          $model = $observer->getData('object');
          $this->getRequestInfo()->addModel($model);
      }
docs: Listens to model_load_after and records loaded models
  
  @param Varien_Event_Observer $observer