Half-roasted chicken is the dish you order at a restaurant when you want to know whether the restaurant can cook. There is no technique to hide behind. The bird is the bird. You either understood the brine, the air-dry, the high heat finish, and the rest — or you served a chicken that nobody at the table will remember.
Sieger Bayer runs bar Berria in Chicago. The whole roast chicken at bar Berria is, per several local writeups, the dish to order. Which means he has cooked thousands of them, watched what the skin does at every temperature, and developed the kind of opinion about chicken that you cannot fake.
Bobby grills. The half-roast is not a grill move. It is a low-then-high oven move. He was on someone else's terrain.