Yes, definitely a surface effect.
The current state of the art is like striking steel to see if it will throw off sparks. Sometimes you get lucky. I’m assuming Rossi has figured out a process to “tune” the nickel. I’m guessing he found a process to make nano particle nickel of a shape or size that easily causes a LENR reaction to take place.
That would also explain why you have to “recharge” the reactants. As each region of the nano particle undergoes the reaction it will melt or even vaporize, destroying the structure required to create the initial reaction.
No one on this thread has answered why they won’t allow radiation detectors, because there isn’t any.
Might as well be from a science fiction novel.