The manx rumpies do not have a lethal gene like the araucana, that is only in the tufted araucana. Manx rumpies also lay a white or pale tinted egg not blue. I think somewhere it said that 1 bird in 1000 laid a blue egg and there was belief that it had been mixed with araucana some where.
90% of the worlds araucana do not have a lethal gene. It is only the tufted araucana that are bred to tufted araucana, that can cause lethality, because it takes two copies of the gene to be lethal. The araucana are not a commercially viable bird to breed because of this and because of fertility issues due to lack of a tail. This is true for the manx rumpies also.
So anyone saying they don't want to give araucana a try because of the lethal gene need not worry. Just buy cleanfaced birds and only breed for the cleanface. They would not be up to standard, but the would lay a beautiful egg, be rumpless, sweet, good foragers, hardy, dual purpose as they have a nice breast when grown. They lay all year long.