Adequate support and training eliminates power users
Power users evolve when organizations don't have adequate technical or organizational support. You need a responsive help desk with a reliable tracking process to ensure help requests aren't dropped. Training doesn't have to be centralized, or even in-house, but it needs to be accessible. Help desk workers are trainers by the nature of their position. They are the face of your IT organization and should be as carefully chosen as your system, network, developers and database people.