Access clean attributes

Is there simple way to access clean attributes of DS.Model? For example, for the case when currently editing model displayed somewhere in the header. It looks kinda ugly when unsaved changes get displayed right away. As far as I see from InternalModel definition, there’s _data property containing persistent attributes, so I tried to bind a computed property on it (naively). Obviously, it didn’t work. My previous workaround involves maintaining parallel structure for clean attributes which turned out to be unreliable for a number of reasons. Any better ways to achieve that?