Regarding the blue SBT's.....I think you will find that the pigment colour is actually a dark grey, appearing black against the blue coat, it is genetically impossible to get black pigment on a dilute. This is the reason most SBT breeders avoid blue, it does not conform to the breed standard, which calls for black pigment. On another forum I saw photo's of a blue that they always thought had black pigment, but when photographed next to a dog with black pigment, you could see the subtle difference.