[candiodari]

ITER has done heroic design efforts over the past few years. But you'd be disappointed how small the resulting changes were, but they were heroic efforts. Things like feedback systems for plasma containment. So to your question, the answer is no. ITER cannot be retrofitted to use HTS materials. Effectively they cannot change the materials they use, nor can they change the shape of the superconductors. If you can't do that, there's no real point to switching to HTS supply.

The problem with ITER is that it's being half-ass funded. It's only enough funding to build it over 50 years or so. We could spend 3-4x the amount one year and have it built in 2 years instead and we wouldn't be asking these sorts of questions. We would know (that it doesn't work - I'm not a believer. However, I do agree that a massive amount of plasma physics will be learned with it after it fails to Q>1).