Bunk! Graphite is a poor conductor compared to most metals. It is less conductive than NiChrome which is designed for higher resistance.
You completely misunderstand. I was speaking specifically to people with metal metabolism disorders, like those with Wilson's disease.
It is extremely irresponsible to encourage people to use copper electrodes without warning them of the side-effects. Are you really going to encourage people with Wilson's disease to use copper electrodes? A single minute of zapping with them could send a Wilson's patient into immediate liver failure. The conductivity of this metal is irrelevant if it will KILL them.
That is why they should use graphite electrodes instead. It is better to zap with them than not zap at all.