Cold fusion has required physicists to consider chemical issues, which seems to be a problem for them. In a chemical system, the energy is distributed in several different forms, but with the potential chemical reactions limiting the magnitude of each form. For example, the enthalpy of melting limits the amount of energy present as the so-called phonon energy. For example, it's not rational to pretend that 23.8 MeV can be dumped into the local phonon environment without massive local melting being the consequence. Normally, nuclear energy is dissipated and converted to phonons well away from the source and throughout the general environment by means of the radiation converting its kinetic energy to heat. Why would cold fusion be different?
In any case, energy is not an absolute. It is always measured with respect to two states or conditions. Also, energy only flows down hill. So, when THH says that lots of energy is present, his comment is not useful unless the source is identified.
In fact, a chemical system tries to go to the condition of the lowest energy. The attempt fails only because some conditions having a lower energy may require an activation energy. Consequently, this energy is not available until the activation energy is supplied. If you want to use this source of energy, you need to identify how the activation energy can be applied. For example, increased temperature causes the fusion rate to increase because it supplies the activation energy for diffusion, which limits the supply of D to the fusion sites. This explanation has been demonstrated to be correct.
Also, the chemical energy states do not interact with the nuclear energy states. That is why the idea was rejected as being impossible. Obviously, this rule does not apply to cold fusion. We need to discover why not.
So, we have several basic rules that MUST be applied. Pretending they do not exist has kept a useful understanding from developing.