HHGttG - was Re: WTF is Saskatoon?

[fahrvergnugen at cox.net (fahrvergnugen@cox.net)]

---- Chris Bennett <scirocco16vr32@gmail.com> wrote: 
  I have
> heard way too much arguement from both sides and will happily point
> people in directions to read more.  It is hard to speculate why Gaff
> (Edward James Olmos) left the origami unicorn outside Deckard's door
> if he didn't know that Deckard was a replicant...

  I have not read the original story, but have a copy of the DC of the film.  I have always thought that he left the unicorn to let the replicant Rachel live, either because he had sympathy for her, OR because he knew that she would be different than the rest what with the memory implants.  Or a third possibility, he was sick of killing?

I ask only because I am unfamiliar with the book.  Where do these possible explanations go wrong with the written story in mind?

David