its the same with any animal/person.. if you only ate one thing your entire life.. sure you could be well fed.. but you would be lacking in some essential vitamins and nutrients.. chicken bone is different to mammal bone.. its less compact, and has a smaller blood supply, and the marrow would be a higher percentage if you were only feeding drumsticks and wings, which can become a bit 'fattening'.. a chicken wing/leg has mainly muscle, all blood drained out, ligaments, bone and thats about it.. a rat has everything, small bones/big bones/ partially digested food/organs/ blood etc.. id ASSUME, and correct me if im wrong that a diet ONLY consisting of chicken legs would be lacking in iron (as the blood is drained), calcium (as the percentage of calcified bone/ bone marrow is different in a single long bone), and many of the vitamins found in the gastrointestinal tract of the prey, as well as many fats (depending on how chubby the chook was)...and im sure there are others.. there is always debate about rats vs mice for nutritional benifit.. If you want a happy healthy snake, its best to feed as closely to their NATURAL diet.. this means a combination of many different prey items.. this is not always achievable in captivity and supplementation of feed stuffs can help to offset the nutritional deficiencies in some feed stuffs.. my snake wouldnt eat for a while, and i had a ckicken neck in the fridge, intended for the cat, but i gave it a go, made sure there were no sharp edges, and even made one end pointy by squishing the meat up, and the other end have a 'tail', from a bit of the muscle...lol.. it was mainly for my own amusement, and im sure my snake didnt care, but she loved it... it was enough to get her started on mice again, and now she is on rats! Variety is the key.. but if you supplement correctly, a diet primarily on chicken pieces 'may' work, however my worry is potential internal damage to the snake fater swallowing a cut chicken leg/wing/neck as the bones can be pointy and sharp where they are cut..