This tactic is seen when one demonstrates that they know what they can offer, and have a thorough understanding of what the other party brings to the table as well.
Consider the previous example under “Curiosity,” where the negotiator claims she "keeps people out of jail." The follow-up allows her to display her knowledge of the law, opening a discussion of felonies.
It is not always necessary to counter this tactic, but don’t take others’ claims of expertise at face value. Are their claims and statements peer-validated? Check references and ask around in the community to get a clearer picture of your adversary.