It's not necessarily silly as idea what they did. In fact, it is also the AIrbus patent principle that were inspired by Holmlid. Monoatomic hydrogen created by discharge and low pressure condenses on a semiconductor surface doped positive by additives. These electronic holes are supposed schrinking monoatomic H by deforming, I think, electronic orbitals.
Fabrice's ( fabrice DAVID ) papers on the 'fusion diode' are now available as a bulk download:- here's the abstract
EXPERIMENTAL RESULTS WITH SOLID STATE FUSION DIODES
The authors present a different approach to prove the reality of LENR: the Fusion Diode. This device has no input energy, relying on the only energy produced. The diodes are fabricated as powder diodes, with a large surface junction made up of a semiconductor in contact with palladium charged with deuterium. The suspected fusion reactions take place in the junction between the semi conductor and the Palladium powder, which produces an excitation which is transmitted to the electrons.