Het Ivory = Yellowbelly
Heterozygous Yellowbelly = Yellowbelly = Het Ivory
Its all the same thing just semantically incorrect. I call them yellowbellys because thats what the first person who produced them calls them.
I personally havn't met or heard of one geneticists that breeds ball pythons.
I may not have a degree, but have taken more than my share of science and Biology classes. Through high school and college I have taken 8 Biology related classes, which all undoubtedly deals with genetics.
I agree genetics is confusing and when have I ever said to a new person thats a het pastel or event tried explaining it to a new person? I havn't. When I see people mocking others for their own incorrect information is when I try to educate some people on the basic terms of genetics, which is all this discussion is.
Not saying you mock, but others do.