The only clutch I've seen with supers was from unrelated cinnamons. One baby had duck bill, a kink, and a curly tail and the other just a little bit of odd snout. I also assumed it doesn't have anything to do with inbreeding to be showing up regularly in something as outred as a co-dominant mutation. However, I think it was TSK who posted that they have had good luck avoiding this problem by breeding black pastel to cinnamon. That was really unexpected to me as it looks like the problems are just a side effect of both mutations so I don't see how the combo would be better than either line by it's self but of course practical experience is more important than what I can imagine.