I wouldn't think so either. I think it works for lights, but not sure how it would relate to darks. There is probably some way to breed more color in, especially in the hens. Maybe select for the darker color rather than the steel gray in the hens? It seems like I see a wide range of penciling on the hens. Some are barely visible and some are very obvious. I'd be interested in hearing how the dark breeders keep the color strong. I think I'll have to play with the chicken calculator and see if I can't find it.Not sure....I don't THINK so.
There is an excellent example of what is NOT to standard selling some hatching eggs on ebay right now.