I agree with Centaurus. If you consider that the terms 'pilot', 'First Officer' and 'Captain' all come from nautical usage, can it not be assumed that similar nautical practices would also apply?
The pilot steers the ship as per the Captain's command, and that should be without question. However, I don't really believe that anyone would take offense if asked why a decision was made if discussed after the flight in the bar, and that is really the co-pilot's opportunity to learn and develop.