I'm not going to do things I deem harmful to a child. Varying discipline techniques, aside from spanking, sure I'll try. Different sleep methods/routines, sure! But I will not harm your kid. The occasional cookie, I'd keep my mouth shut. Some food is better than none. Cookie every day instead of lunch, nope. I'd propose a solid method for getting him to eat, and if they balked, its time to move on.