The only drugs I've heard Jon doing was Cortison and that was for his voice. Jon has been quite vocal about not doing drugs and not seeing the point of it. I've never read him or any of the other band members (except maybe Alec) doing any drugs. They didn't think TD was that dark when they recorded but it just happened to turn out that way. I think that is more the reason for them not playing the songs as they are not really uplifting songs for a concert.. not because of a drug problem!