"Titanic" director James Cameron is conducting his own test to find out once and for all if Jack would have lived had Rose left a bit more room on the floating piece of wood at the end of the 1997 movie. The test is featured in an upcoming National Geographic special called "Titanic: 25 Years Later." Cameron simulated what Jack and Rose went through in the freezing North Atlantic waters. He even chose stunt doubles with similar body types to Kate Winslet and Leonardo DiCaprio.