Would certainly be a way of proving whether it works or not. As I undertand it, the principle of it is that the "spirit" guides the movements of the participants fungers to spell out words so the pliving participants' ability to spell should be irrelevant. All we need now are a group of illiterate participants - when does football season end?
Nah, it's the collective unconcious will of the participants that makes it work. It'd only be if they're all secretly willing the same thing - therefore if they're illiterate they may know who they want to contact, but not how to spell their name. That's why there's so many phenomenonal situations where a group of people set out to contact a specific person and "actually do".