Oftentimes group participants have had many experiences with treatment activities. They also have an abundance of experience with therapists and social workers. I find it useful to make it clear that their previous experiences will be different in Thinking Matters. There are no "war stories" or platitudes. No discussion of "off topic" subjects.
When it becomes clear that the facilitator understands what is unproductive, participants take the group more seriously. They become more open and honest. They develop a sincere curiousity for their own internal processes.
The interesting part about teaching Thinking Matters, it directs you to also look into yourself and changes can be made (however minor :-)).