Deckard not a Replicant?
If, as so many argue, Deckard was not a replicant, then why:
1. The origami unicorn (seen in Deckard's dreams) left by Gaff? Gaff had access to Deckard's implanted memory.
2. At the ending, both Rachel and Deckard are in the car dead. Their replicant time to expire had arrived. This is mentioned in the film as a safety feature built in to replicants in case they make it to earth. Even if they aren't found, they will eventually cease operating. If Deckard was not a replicant, then why is he dead?