You can register different types of HumanTaskHandlers. In the emergency application I've used the CommandBasedWSHumanTaskHandler because it gives you some extra features for different environments. You are true, in my application it didn't have the "Human Task" string in my BPMN file, but that's because I was using an old schema where you need it.
Right now you need to register the "Human Task" workitemHandler with one of the TaskHandlers implementation in order to work.
Sorry for the confusion.