But a guillotine doesn't deliver more energy that a nuclear explosion. Given the endothermic nature of splitting helium it would have do the splitting and the exploding.
I'm so sorry, but you don't split (fission) helium to get energy. You combine (fusion) helium to get energy. You split something heavy like uranium to get energy.
The point is the "energy well". That is the elements "in the middle" of the periodic table are more stable/at lower energy states. So fusioning heavy elements or fissioning light elements move to higher energy states, so it will take more energy in than it releases.
