Yeah, I liked the idea that it's asymmetrical. You use the VK to find replicants trying to pass as human, but to try to make sure they're sufficiently robotic you need something else. Which makes sense: the original VK would be easy to tank if you were _trying_ to act like a replicant.

And narratively I think it works amazingly. The idea of forcing someone to prove that they're sufficiently inhuman ... shudder.