It's still not really in the employee's interest to reveal their above-average salary history until they've gotten a salary range from the employer first. After

It's still not really in the employee's interest to reveal their above-average salary history until they've gotten a salary range from the employer first. After they get that range, they can choose to reveal their salary history if they think it'll give them leverage in negotiations (e.g. if they want more than the high end of the range), but anyone who's happy with the offer they get won't have a reason to reveal their salary history even if it's above-average.