That code change is great - I’ve been trying forever to figure out why this happens.
The question I had is whether or not this affects any of the performance gains afforded by instanced stereo rendering. I haven’t gone into the rendering pipeline to see how this change would affect the actual rendering, nor do I know very much about rendering at all, but if they intentionally left off the EyeIndex = 0 case for performance gains, this obviously negates those gains.