"Loss" is the term we use when we want heat, but it's going away against our wishes. The correct term for generating and eliminating unwanted heat is "dissipation".
That this is the intended meaning is clear from the later wording "... being able to conduct electricity without generating any waste heat".
> What happens if I put 200 amps through a thin stand of it?
That's a good question. Even if a material can carry some small current with apparently zero R, that doesn't mean the same R value applies at a high current. It could be non-ohmic, that is.
If you want to read the details on how it works, I suggest this paper [1] "Large-gap quantum spin Hall insulators in tin films". The real hope is that this will be a replacement for the conductors in traditional silicon. You still have the heat bottleneck when you hit a traditional conductor. The dissipation free property breaks down at about 100C for this material, so you are going to have an issue with what ever is interacting with that 200A.
[1] http://arxiv.org/pdf/1306.3008
That this is the intended meaning is clear from the later wording "... being able to conduct electricity without generating any waste heat".
> What happens if I put 200 amps through a thin stand of it?
That's a good question. Even if a material can carry some small current with apparently zero R, that doesn't mean the same R value applies at a high current. It could be non-ohmic, that is.