Quote: You are absolutely correct. Only recessives are referred to as split. Split is heterozygous--but with a recessive, there is no way of SEEING it--you only know it is present because of breeding records--one parent was homozygous, therefore it MUST have the recessive gene that is not apparent in its appearance.
A black has no dilution genes such as blue. A blue has one copy of blue and a splash has two. Blue X blue will have 25% black offspring. Black X black will never have blue offspring. A black will never have splash offspring.