As outlined by Craig Weber, conversational capacity is made up of curiosity and candor.
For difficult discussions to be effective, we need to be curious about possibilities beyond what we believe to be the best solution and we need to be able to articulate clearly what we believe, the data we are using to support our belief, and how we are interpreting the data (our ladder of inference).
This assessment allows members of a team to assess themselves and each other on both curiosity and candor. Team members (including the team leader, if there is one) can compare how they rate themselves to how others rate them.
You may download sample reports (disguised data from an actual team) here: