Dominant is not defined as "when paired to a normal you get nothing but the visual het version of that snake." That's the definition of Homozygous. Homozygous means having two copies of the same gene. If that gene is dominant then you get nothing but visual hets that are the same phenotype as the homozygous parent. If the gene in question is co-dominant then you get nothing but visual hets but that visual het has a different phenotype. That means that they don't look like homozygous parent.