User blog comment:Subject 16*/Assassin's Creed: Revelations - News/@comment-3979092-20110508003220/@comment-1655340-20110508005718

AND, as someone brought out below, when Subject 16 said "find me in the darkness" when you conversed with him after finding all the rifts in Brotherhood, there is a possibility that he is referring to the "black room" failsafe that Desmonds finds within the Animus. So, it's possible that, while the black room lets you see Desmond's life, we may also find Subject 16 as well.