Here's something that the original article did not really discuss...
Most of science proceeds by small steps. Someone notices an anomaly. Someone manages to repeat it. Someone manages to extend the current theory to fit it. Someone may come up with a radical theory that also fits. Someone finds another prediction from the radical theory, and looks for verification of that. And so it goes on.
We know that there is a large potential barrier to getting light nucleii close enough to fuse. We can whack a few particles into each other in colliders and explore quite how hard they are. This tells us about the particles and forces involved, but colliders use a lot of energy, and we get almost none back from any fusion. We can try things like stellerators or tokomaks, which are designed to provide lots more collisions of one particular type much more efficiently, and work towards break even. The two positive nucleii will repel each other, but we can replace the electrons with mesons, which are more massive and sit a lot closer to the nucleus, so that gets around some of the electrostatic repulsion; but mesions have a short half-life so we have to keep making the things. All this is not very successful, but it is logical.
The bit that is never explained is why Fleichmann & Pons expected to produce fusion using electrolysis. Or why Rossi expects whatever he does to produce fusion. What was the anticipated process that provides the squish that gets the nucleii together close enough to cause fusion in their experiment? We know a lot about how much energy or force this takes. We also know a lot about the decay particles that we would expect from fusing particular atoms. It could be that there is some entirely novel means of doing this, and some entirely novel decay modes. As scientists, we are required to hold this as possible in principle, but we do not generally do experiments without a credible positive outcome. If you are investigating a small anomaly, such as the 'extra' energy in the F&P experiment, you investigate an unknown: you do not attribute any energy difference in advance to fusion by an unknown process. William of Ockham had a thing or two to say about this sort of reasoning.
Compare and contrast this with the supraluminal neutrinos investigation. An experiment seemed to say that some particles were travelling faster than light. The likely explanation was that there was an experimental error. The error corresponded to several meters in length at the speed of light (a surprising error, but possible) or a timing error (a few nanoseconds, much more plausible), or something else (including the stated remote possibility of a faster that light particle, which would upset a helluva lot of physics, and no-one really believed). They performed tests to verify their surveying and timing assumptions, and found a timing error in their electronics. A lot of science is dull like that.