Just found this thread and have not read all of it so if this is a repeat, my apologies.
Rather than answer this question myself, I suggest you ask the passengers and crew of the ms Prisendam. Seehttp://www.qsl.net/n1ea/
for full story and links to audio of messages sent. Literally NO voice, data, or satellite mode worked. Only the ability of the marine ops to send and receive CW save the 535 souls on board. Code is now no longer required on our ships yet it is still saving lives, recently a small craft in Britain sent an SOS (no longer considered a distress signal - yeah, right) via flashlight to a passing helicopter and got their coast guard to help.
Any mode that can get thru is an EMCOMM mode. By definition, if it is an emergency normal things won't work so why all the angst about using code to communicate? Simply amazing that those who do not know enough about CW and its capabilities want to scrap it to be replaced by nothing of equal ability. Sad really.
Just my not so humble opinion of course.