Re: The numbers are not tautological.
The coil is not insulated so where the superconductor doesn't work it conducts through the relatively high resistance underlying substrate.
A quote from the source .....
The fundamental problem of REBCO is that it's a single-filament conductor that cannot be made perfectly," said Larbalestier. "So any length of conductor contains a variety of defects whose impact on any future magnet is not yet well understood".
Biting the hand that feeds IT
