I would rather sit in my CP's office explaining why I declared an emergency for a situation that turned out to be a non-event than sit in that very same office trying to explain under what medical training I had determined my passenger would be fine while the media has our colours all over the place with stories of a dead passenger.
I've never understood why some pilots (and passengers) feel that declaring an emergency or asking for priority through the internationally accepted means is tantamount to incompetence, or at the very least severe overkill.