Don, ever since you pointed this out to me, it has become more and more obvious on my rooster. I even found a picture of Wade Jeane holding one of his roosters, and the bird in that picture had the same exact comb flaw. I'm afraid it is deep into the line.The Penne have been bred into the Marans since they were brought into the USA. I would believe that some beginners are still doing it with the aspect of getting darker eggs.
For comparison, I put a picture of my rooster beside a penedesenca, and it is very obvious that is where he got his comb
Mine
Penedesenca