So if you have an X variable cure, that means that an X-1 variable cure is not enough, right? I'm not very familiar with the nuances of the scientific process,

So if you have an X variable cure, that means that an X-1 variable cure is not enough, right? I'm not very familiar with the nuances of the scientific process, but I would think that you could still run tests on one variable at a time. Just turn all but one variable "on", make that your control group. Turn all variables on, that's your experiment group. Now repeat the process isolating each variable, determining whether they're all in fact necessary for the cure.