Chiefio has posted new hypothesis that is worthy of thought and testing.
Based on angstrom dimensions
Probably testable more easily than some other hypotheses
The hydrogen squeezes into the lattice cage. Temperature rise makes the hydrogen expand to two to three times.
Energy as vibrations is pumped in(acoustic? THz? laser, e/m fields.)
The H is forced to merge with Nickel, or other transition metal( as in Piantelli hypothesis)
think I remember Bob Greenyer saying "why Nickel?".."because it's heavy!"
but maybe he should have said "because it's big"
Probably has some relation to catalysis in molecular cages concept.
When you squeeze energy into confined spaces you get .. la bufadora!
My slant... what happens if there is big uranium(+4)elephant in the lattice..as in zircons