There are only a few people today that are currently working with the recessive leather gene. From what I've seen, the only breeders consistently working with them are Tammy at Draggintails, Inc and Josh D. at Phantom Dragons (the one who "created" the recessive leathers). Not to say that others aren't (for example, I know that David at Carolina Classic Dragons has a future breeder/breeder that is both a recessive and co-dom leather), but those are the few breeders that have consistently listed them in the past, that actually know what they're talking about.
Genetics 101:
Co-Dominant Genes (Italian/American co-dom leathers)-
Leather X Normal-Scaled animal= 50% leathers, 50% normal-scaled, NO hets
Leather X Leather= 50% leathers, 25% normal-scaled, 25% super form (silkbacks)
Dominant Genes (Dunners)-
Dunner X Normal-Scaled animal= 50% dunners, 50% normal-scaled, NO hets
Dunner X Dunner= 100% dunners (seeing as no one has bred a dunner to a dunner yet, it is still possible that dunners could end up being a co-dominant trait)
Recessive Genes (recessive leathers, hypos, trans, witblits, axanthics, etc)-
Recessive leather X normal-scaled animal= 100% hets
Recessive leather X recessive leather= 100% recessive leathers
Recessive leather X het. recessive leather= 50% recessive leathers, 50% het for recessive leathers
het. Recessive leather X het. recessive leather= 25% recessive leathers, 50% het. for recessive leathers, 25% normal animals.
I hope that helps to explain the genetics of these animals better.