"He said Sammy"
Ever since I saw this movie in the theater and the dozen times I've watched it since, I always got confused when Leonard drops Jimmy and says "He said Sammy," which is a realization that he had told Jimmy that story at some point. Jimmy never mentions Sammy before Leonard kills him so I didn't understand where that came from. So I watched it again last night and finally realize he hears it immediately before he drops him.
I guess my question is did Leonard imagine this or did Jimmy somehow call out Sammy's name after he was already dead?