Hair tagging in monochrome art

Since hair in monochrome art can't be tagged by color, would dark_hair and light_hair be useful to have? They would also implied by dark color hair tags (black, brown, redheads) and light color hair tags (blonde, red dyed, bright blue, pink, etc.)

This is probably a dumb idea but I'd rather keep flinging ideas at the wall until something sticks than be a passive user of this site.

No. True monochrome images have specific ways of illustrating different colors of hair and would require obscure tags not many people would even think about. And besides, who looks for specific shades of grey hair in greyscale images?

I'm with tapnek here, it's better to not tag it at all.