I'm aware that the saying is different than its historical context - it's not as if the captain was supposed to commit suicide if his ship sank, he was just supposed to be the last man off the boat.
Still though, it seems to me like this would be a colossal waste of maritime experience and knowledge, especially during a war when you can't just train new admirals at your leisure. Shouldn't the captain be the first man off the ship?
Also, why is the idea of the captain actually going down with the ship romanticized so much? If you've ever seen "Perfect Storm" then you know what I mean. It seems like popular culture takes the saying quite seriously.
The captain is supposed to remain onboard in order to help coordinate evacuation efforts.
One interesting case that seems to be cited as an example, although a bit complicated, is that of Howard W. Gilmore who was wounded on the bridge of his surfaced submarine and ordered the ship to submerge in order to save the rest of the crew. He was awarded the Medal of Honor.
http://www.history.navy.mil/photos/pers-us/uspers-g/h-glmore.htm
Recently, this was why the captain of the Costa Concordia was vilified and some of the charges brought against him included abandoning incapacitated passengers. He had fled the ship early which delayed rescue efforts.
Is there truth to the notion that the captain on an old merchant ship was financially liable for the fortune he was transporting while it was under his care, and therefore if he lost his boat and survived, he was ruined? I would find that a motivator to take extraordinary measures to save my ship, or die trying. Kind of like the whole Spartan soldiers and their shields thing: come back with it, or come back carried on it.
You might be interested in these older threads.
Who took priority on a sinking ship? An upper class man or a lower class woman or child?