I think if light affect the POI on any scope, then the long rang boys would be screaming about it now. I don't see how light can change the refractive index properties of a scope. This one example, with a clear fault, however unknown, I don't think is safe to extrapolate a theory about all scopes from.
The 1000yd F class boys are working to an order of mm-cm even at that range... i think it would have been discussed before... especially as they're well aware of POI shifts due to mag changes or dialing inconsistencies etc
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