I too, have never seen an overcooked hardboiled egg. I have them for lunch everyday at work. My DD bought me a Henrietta the Hen egg cooker. You can poach, soft boil, or hard boil eggs. You just put the right amount of water in, and Henrietta does the rest. Generally speaking, the fresher the eggs, the harder they will be to shell when hard boiled. I shelled 6 last night, 4 were perfect, 2 the white stuck to the shell. Same carton of eggs, who knows?