Politics can be brutal. If you run for office, you should be prepared to face your toughest critics and have your dirty laundry aired. As a serious candidate, knowing the bad choices you made, you can pre-empt your opponents attacks by addressing your negatives and turn them into something positive.
As people we have our faults and we have regrets -- things we wish we had a do-over for. Both candidates for President of the United States (in 2016) have their faults and I am sure, their regrets. I believe it would benefit Hillary Clinton's campaign, and she could swing voters her way, if she was upfront with her negatives -- address them and take away any ammunition Donald Trump and other potential Trump supporters may have in this campaign.
By addressing our faults we take away the power of our opponent to use them against us. As voters, we can appreciate that we are not perfect and sometimes we make bad choices. Admitting that we made a bad choice, rather than run from the issues speaks volumes about your character and your ability to be a leader. Avoid the issue, fail to admit your wrongs and you can end up making a bad problem worse.
If the Secretary of State deals with the issues that voters are skeptical about in the first place, she can put any rumors to rest, and take away any talking point Donald Trump may have against her.