User blog comment:The Crimson Eagle/Assassin's Creed: Revelations Review/@comment-5336493-20120726175444/@comment-4928711-20120728125227

Yes, Desmond didn't know, but the Animus made him view those memorys because at that time Ezio was viewing Altair. He could have viewed any other memory. How about that gap inbetween ACB - ACR.

"That, is a Sync Nexus. Find it, and the Animus can separate Desmond from Ezio and ALTAIR and send you home – back to your body."