Your not getting the point if they are different genes then when bred to a normal you'd have a 1:4 shot at getting a BEL, like with any other animal that carry's only one copy of two "different" genes like a Bee or a Pewter or a Blast ect ect ect.. So because you don't get BEL's from a Mojo Lesser BEL to normal the BEL is the homozygous form of that "gene" its just that the gene is diluted in some animals.. Lesser and butter is the same gene just different expressions of it..
Same thing with Superstripes....Superstripe to normal doesn't produce Superstripe's it only produce YB's and Spectors.. so a Superstripe isn't a combo of two genes but rather the homozygous form of the same gene in a dilute form.