If you read further, they claim that the reaction isn't permanently sustainable, and that the device needs to be refueled periodically (on the order of months).
They go on to claim that 90% of the nickel 'used' can be reprocessed into reusable fuel, so there is an ongoing 10% loss.
Yea, I know, it is still funny, you wanted to know what is funny so I told you.
I real scientist/engineer would never flop a question like that.
By the way, Rossi got his degree from a diploma mill.