Quad het just implies that you're dealing with different versions (alleles) for four different genes. Let's simplify things just a bit for discussion by looking at only one gene. If an organism is heterozygous for that gene, it means that it got one allele (let's say a "dominant" allele) from its father, and a different allele (let's say a "recessive" allele) from its mother. Dominant genes normally dictate the appearance (or phenotype) of the animal, so heterozygous individuals look just like individuals that have two of the same copies of the dominant allele (or homozygous dominant individuals). I know that was a mouthful, so in other words, hets look just like non-hets with dominant alleles. Only individuals with two copies of the recessive allele (homozygous recessive) normally have a different appearance (or phenotype).
Getting back to the quad het, you're dealing with at least four different genes that have different alleles (versions of a gene) at all four sites (or loci). Knowing the genetic make-up (or genotype) of heterozygotes is very difficult, even if you keep strict and meticulous records, unless you conduct genetic analysis, which takes sophisticated and expensive equipment. Why? Because hets look just like homozygous dominant individuals. That's why most people talk about the "probability" of having hets.
Here's a link back to one of Scott's web pages where he discusses hets (
Scott Felzer's Garter Snakes). I know this is a difficult topic, so hopefully Kitkat (and perhaps others) can take a fresh stab at explaining it more clearly. Hope this has helped, though.
Rick
P.S. The "wild type" or wild color is the dominant appearance (phenotype). It is the opposite of these traits, so it's not counted as one of the "quad" genes that are heterozygous. Also, Daniel's description sounds reasonable, but please let us know what Scott tells you.