As I mentioned elsewhere, I am experimenting with LED lighting.

I was having a curry with a former colleague last night, who mentioned
his father hates LED lighting for the following reasons:

1. The spectrum is too narrow thus depriving the body of the right
kind of light.
2. HIgh frequency flicker, higher than fluorescents possibly
triggering migraine.
3. Because of the frequency (colour temperature?) the light does not
travel as far so streetlamps need to be placed closer together but.
Councils are not doing this for cost reasons, leaving blackspots in
illumination.

Is there any merit in these arguments?