The familiar group should still make room for an unfamiliar answer.

Groups that have worked together for years develop a shared sense of what a sensible answer sounds like, and that sense gradually does the filtering thinking used to do. An unusual suggestion gets dismissed by tone rather than by argument, often before anyone has considered it. The comfort of the group is genuine and so is the narrowing. Familiarity makes agreement quick, which is useful for routine work and costly for anything new.

In the next familiar meeting, hold one odd idea for a full minute before responding. Asking what would have to be true for it to work tests it instead of dismissing it.