If system is bad it doesn't really matter how many people in the system are ''good'' or ''bad''.
This comes to mind:
“Democracy is the worst form of government, except for all the others.”.
First improve DT system, than ask people to join or leave.
I've seen several suggestions, and my favourite is still to require more than one DT1-vote to reach DT2, but I doubt there's a perfect solution.