Ray,
I think more often than not when a ship is refered to as ' the ' something or other, the person is being " familiar " rather than " correct ". ie When someone asks , What ship is that ? and you turn around and say ' OH its the Victory or OH its the Cutty Sark.
Its a bit like the wrong use of the word ' boat ' as against ship. In my day, we often used the word ' boat ' as a term of endearment or of familiararity, eg Its a Harrison Boat, or its a Lamport Boat or more famously ' Its a Skin Boat ' ( Banana Boat )
That kind of use of the words was normally used by seamen talking to their own kind, and may probably have been wrongly interpreted and used by shoreside people trying to impress with their knowledge.
Kind regards,
Chris.