I’m not sure to understand the expression “glancing angles” (goggle translator was useless…).
Do you mean when the camera forward vector is almost parallel to the reflective plan?
If so: I asked myself the same question and I searched for images of reflecting marbles. It appeared that you could have clear and strong reflections even if you’re in front of a marble surface if it’s perfectly polished.
But I think you’re right: reflections would increase when approaching to “glancing angles”, just like a glass. And using a Fresnel falloff to increase/decrease would be necessary here. It is not implemented yet in the video.