Example if Romney says oil production on federal land has gone down and Obama says it hasn't and they sort of go back and forth and at times Romney says it's gone down 14% in a year then as they quibble he says it's going down generally and Obama equally being weird about it and says it isn't...and the truth is it went down 14% last year but hasn't gone down net over the presidency...it's not her job to jump in and say "whoa, BP oil spill, also let me explain the lease situation, also there are concerns about the administrations focus as Romney says, also the year stat is right but the trend it is trying to show is misleading, and on and on"....that isn't the role.
If they literally go back and forth over a plain and simple fact of record, she can say it is or isn't on the record.