I don't know for sure, since I don't have one and it's not on the "list", although it is striking. I doubt it is virused. Especially if the vendor is saying only a small percentage shows the phenotype. Sounds like an unstable mericlone mutation. There are several cattleyas with varying types of mericlone splash/feathered mutations. There is also the well-known C. trianiae 'Jungle Feather' that shows feathering on the distal petal edges.