How is that a burden? The controller has to know about the methods of the DAO no matter what. The debate you're having seems to be "what is the best way to get

How is that a burden? The controller has to know about the methods of the DAO no matter what. The debate you're having seems to be "what is the best way to get a concrete instance of the DAO into the controller?" The argument being made for constructor/accessor injection is that it makes testing easier. The argument against it is that it makes the API more complicated than it would otherwise be.