one has to wonder why, if I am boggling around inside a cloud with zero vis, I need to be able to identify aircraft nav lights
TPK, my knowledge of your medical condition is pretty much zero, aside from what you've just posted here.
But one thing springs to mind with regards to why it might (and I stress the word "might" - someone with a medical background could probably confirm or deny this) restrict you to VFR-only. I'm thinking about flying an instrument approach down to minima. You will pop out of the cloud, possibly with very poor visibility in haze or precipitation, and only an extremely short amount of time in which to orientate yourself visually in order to carry out a safe landing. Typically the runway lighting will be turned on in these conditions, and will be a vital part of your visual orientation. Might your condition make this more difficult, I wonder? Clearly the AME who removed your VFR-only restriction didn't think it would be a major problem...
FFF
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