First of all, IMO (& as others have stated), the eye-glow is a plot device, not visible to the characters, & meant to be a "pointer" for the movie-goer. If not, there would be NO NEED for the VK machine; the characters would all have to be complete morons to not just put all the suspects in a dimly lit room & pick out the skin-jobs by taking a gander at their eyes. Easy-peazy-japanesy.
ANYway, I introduced a buddy of mine to Blade Runner a few weeks ago. He liked it, & some of his observations have actually surprised me (one of the first things he said was that every time you watch it, you notice something different).
So, yesterday, he says to me: "Maybe all the Blade Runners are replicants?" I told him that I didn't think so. But his argument (off the top of my head) was that replicant Blade Runners:
1. Would be better able to handle confrontations with other replicants (tougher, faster, etc).
2. Would be expendable (no danger of human loss of life during a(n) interrogation/retirement).
3. Would be easily replaceable (build a new one, load memory implants, hit the ground running).
Last night I loaded my 1080i HD rip of Blade Runner & took some screencaps. They are from Leon's VK session:
Now maybe this is old news, & if so I apologize. But if you click the thumbnails (& then make sure to click the resulting picture to see it at it's highest resolution), Leon's eyes are glowing slightly, but Holden's eyes clearly have the glow (well, mainly his left eye, which is the only one in shadow).
So, my question to the collective is: What say you? Is it feasible that the Blade Runner units were comprised solely of replicants? I hadn't considered it before, but to me it isn't out of the realm of possibility.
I look forward to everyone's/anyone's input.