The role of the Dreamer was to, well, dream BIG! Dream the impossible, come up with outrageously big ideas without any concern at all for reality. Example, there is the annual staff picnic and you are charged with creating the theme and celebration because it has been a great year. You decide you want everyone to fly high with wings so they get a bird's eye view and see the big picture that all of their individual efforts came together for the organization's success.
The role of the Realist, must then make plans - create timelines and calendars to make the Dreamers vision a reality. The Realist must work and act as if the vision is completely possible. They can't simply dismiss the Dreamer's idea as absurd. Example, perhaps everyone in the company will go sky diving or parasailing. (The realist doesn't concern themselves with the reality that it would cost too much to make that happen).
Next, the Critic works with the Realists action plan to completely destroy it- find every possible problem and reason why the vision simply can't work. Their role is to simply look for ways to make the plan fail.
Next, the Critic sends the failed plan - with reasons why it won't work - back to the Realist. The Realist makes adjustments, ex. bring a rock climbing wall so everyone can still get the perspective and stay within the Dreamer's Vision. They send the revised plan to the Critic, and the Critic destroys it again by pointing out the many reasons it still doesn't work - ex. what about the physically challenged or people who simply won't feel comfortable climbing a rock wall.
The Critic sends the failed plan and reasons back to Realist - the Cycle of Innovation continues until the Critic can no longer find faults and concedes that the plan is solid and fits the Dreamer's Vision.
Next time you and your colleagues need to create a new idea, try this out!