Parrots have the fader gene in them as well, and i think both midas and red devil fade, but i think when you cross them not all of them end up fading.
My last spawn was between a female red flame fh (a fader type) and a male Low grade ZZ. Out of around 20 i saved I ended up with about 5 faders, which faded at around 2 - 2.5 inch. I kept two of the none faded cause they came out with nice Flower lines but thats about it, then the rest were all pretty much no good.
But their mother has that delayed fader gene, which made her fade at a later stage, she was about 4-5inch when she started her fading process. tbh when i first got her i didn't know what a fader fh was, or that she was going to be a fader at all for that matter... Its all luck IMO.
I read here on MFK, (I wish I saved the page), but someone was explaining how there are two fader types, those that fade at an early stage in their development and those that fade later. In saying this I didn't end up waiting to find this out, I gave away all the rest of the fry, and culled others, So i don't know if I ended up with any of the later faders. As i said you get lucky, but i'm thinking the rest weren't going to fade.
I guess it goes, if there is more of the fader gene present, (e.g. FaderxFader) then the greater the percentage of faded fry in the end.
Sorry for the long winded response, I hope I helped a little, and im hoping someone else can expand or explain more clearly what I was trying to get at with the fader stages.