That's why I made the uncanny valley reference. The more realistic it gets, the more weirded out we become.IMHO it's mostly due to the fact that human motion isn't really all that fluid. It's more twitchy in nature, even the eyes. I think it's due to the fact that we have to compensate for the blind spot, as well as how muscle fibers move as a unit. So for me that's the dead give away. I did notice some twitchiness in the face muscles that almost sold me, but then when she looked directly at me it all evaporated because as you said the eyes looked lifeless.