Tim, I believe the "coloured" Dorkings are supposed to be the same as the British "Dark" Dorkings. Dark Dorkings would be expected to breed true.
I have wondered about their genotype. They are almost certainly melanised e+ (Ml?), I've wondered about S with Mh?
I'm not sure whether US "coloured" Dorkins have the patterning. In the Darks I've wondered whether, possibly, some secondary pattern genes, maybe Pg, giving the half moon spangling on the breast & patterning on the wings of the females?
UK red Dorkings are not at all the same colour as what is known as red Dorking in US.
I found the dorking site but had to leave for St. Louis. I will contact the dorking breeders. Thanks for your help.
The standard calls for straw colored hackles on the male. I have seen a few pictures of the breed and they look heterozygous for silver/gold. They also have some red/gold in the same areas that autosomal red produces on the males. Same as salmon faverolle males.
I know they are on wild type because the standard calls for a salmon breast on the female. I hope I can pick the brains of individuals that breed the birds.