You just spatchcock the thing and cook to the correct doneness with a meat thermometer and not your Grandmas pre-refrigeration doneness.
Kenji has all the details.
https://www.seriouseats.com/butterfi...h-gravy-recipe
Cuts down coming time a tonne and cooks light and dark meat correctly and let’s you use the back to make stock for gravy. Better all round. You also should roast chickens like this 30-45 min and you have roast chicken.