Do you think this is the source of the ambiguity in the movie? I was never convinced either way, even after rewatching the whole thing recently with the possibility in mind from the start. I think it was well done either way.

If I'm not mistaken, didn't the protagonist receive a Voight-Kampff test in the original novel? I remember thinking at the moment that this was a reflection on how Philip K Dick wanted to assure us that humans were very capable of evil (he was apparently very moved by the Holocaust), that the Blade Runner didn't have the excuse of being an automaton to justify the cold blood "termination" of sentient beings.