I'd be interested in knowing if "Angel Feathers' share the same Locus as the Araucanas tuffs. I know they weren't directly involved in the development in our precious Ameraucanas but even indirectly they could have passed on specific genetics.
For example: In goats, Their agouti locus has 21 different alleles that can be expressed to make the coat pattern. Their white spotting locus has 8+ alleles that control how much white is expressed over the coat patterns.
Like I said, I'm just curious, It's just a guess without knowing much about genetics of beards, muffs, tuffs and the like.