I dabble in genetics, there are others here who are much more knowledgeable. Blue just happens to be one of the genes that interest me and I like blr wyandottes.
Yes, splash laced crossed with gold laced will result in blue laced (I'm much less sure of the inheritance of red vs gold though). This is because of how the gene for blue works. It is incomplete dominant. A single copy of the gene dilutes black to blue. Two copies dilutes it even more, to black.
So if you breed two black birds, you get 100% black chicks.
If you breed blue to black, 50% of the chicks will inherit a blue gene from the blue parent and will be blue. The other 50% will be black.
If you breed two blue birds, 50% will inherit only one blue gene from one of the parents and will be blue. 25% will not inherit a blue gene from either parent and will be black. And 25% will inherit a blue gene from each parent and will be splash.
So if a splash bird has two copies of the blue gene, they will pass a copy on to 109% of their chicks. This means if you breed splash to black, each chick will inherit the blue gene from the splash parent and a black gene from the black parent and 100% of the offspring will be blue.
If you breed blue to splash, 50% will inherit a blue gene from each parent and be splash. The other 50% will be blue.
Silver turns red/gold pigment white. Silver is dominant to gold. While silver is completely dominant, in real life it isn't quite cut and dry in real life. Males with only one silver gene will usually have some gold color leakage.
Silver is also sex linked. It is carried on the Z chromosome (birds are "swapped" compared to mammals-females are ZW and makes are ZZ). So a silver female will always have one gene for silver and one gene for not silver (gold). Silver males could have either one gene or two genes for silver, in the case of birds from a breeder or hatchery it can generally be assumed they have two copies. Since hens can only pass a Z chromosome to male offspring, any female offspring can only inherit a not silver gene from her with the W chromosome.
That's why a gold rooster (with zero copies of the silver gene) over a silver hen (with one copy of silver on the Z chromosome and one copy of not silver on the W chromosome) will create silver males (ZZ, with one gene for silver on the Z chromosome inherited from the hen and one gene for not silver on the Z chromosome inherited from the rooster) and gold females (one gene for not silver inherited from the hen on the W chromosome and one gene for not silver inherited on the Z chromosome from the rooster).
