Thanks that’s interesting. If it’s so hard to determine if a substance is superconducting, does that mean many substances that are apparently but not quite supe

Thanks that’s interesting. If it’s so hard to determine if a substance is superconducting, does that mean many substances that are apparently but not quite superconducting have similar applicability? I.e., if you need superconductors for X application, can you not just put the substance in question in that application and observe if it works or not? Sorry for the dumb questions.