I must contest your premise (and article title). No matter that it was bred to be pleasing to the eye, may have a slightly different taste and nutritional make-up, it is still kale!
I grow ornamental kale and cabbage because not only is it extra tender, succulent and mild, but it is also ornamental. Same goes for ornamental peppers, eggplant, red-flowered snap beans etc. There is a misnomer out there that ornamentals are somehow no longer the original plant or actually become poisonous because they're pretty. Not true!
Great article on a vegie that has risen out of obscurity in the past decade on the back of it's virtual storehouse of nutrients and easy culture.
Even a gardening Lucrecia Borgia couldn't kill a kale plant!
Okay, now I've read more of the threads.
Agreed, "ornamental" peppers are grown for their beauty more than their taste or eating use. The same is true of the Sweet Potato Vines (and we grow myriad varieties commercially) FOR their ornamental use. The same would be true for our fall ornamental cabbage and kale.
From what I understand though, ornamentals COULD have food use. The one caution is that food grown for eating is often more carefully grown re. pesticides and fertilizers. Once a plant joins the food chain, there may be greater restrictions on those products, right?