[Sombre]

There are a bunch of ways I could explain why they're immobile. They might have all been horribly crippled during the civil war, they might have sworn never to leave their chair or book until the Aufklarung finally consumes the world, etc etc.

Anyway, I'm just putting ideas out. Immobility would solve the communion thing,... well providing we want it solved that is,... and it would help differentiate them from black acolytes and priests, who are like wandering preachers/rabble rousers right now. It would however make them slightly boring and merely functional research units.