I found this article interesting. It seems as if our insulin needs are dictated partly by the secretion of glucagon. If glucagon is taken out of the equation, insulin becomes much less necessary? Yes, let's try this on some humans and see if it holds true. They are calling it a possible cure for Type 1 diabetes.
It's tricky because right now glucagon helps to protect us from severe hypoglycemia. I don't know if I would want to give mine up... it could change the way all the mechanics are understood.