didDocument says "MUST be a DID document that is capable of being represented", but https://www.w3.org/TR/did-resolution/#did-resolution-options says "The DID resolver implementation SHOULD use this value to determine the representation of the returned didDocument", which implies that the resolver is returning a serialized document rather than a parsed one. Which is it?
From w3ctag/design-reviews#1157 (comment)