Context: This above and this aren't a major comment but more of a point for discussion, as I want to learn more.

As far as I can tell, the Protocol Buffer stack would already ``panic()`` on its own if this wasn't guarded, thusly it wouldn't be a defensive check that we'd have to implement here.  Another question: Would there ever be a legitimate condition whereby some should really expect the state to be such that ``DecodedVal == nil``?  That just sounds like a design/illegal state error to me.

What do we know for canonical examples of handling this behavior/scenario?