Their spin often takes the form of accusing others of what they themselves are guilty of.
I suspect the democrats knew this would come out eventually, and feared its impact would be far more damaging in the fall right before the election. So they pull a clinton favorite tactic, leaking it themselves in July, in hopes it will burn itself out well in advance of the election and counting on the American public's short attention span--all the while hopping up and down and squealing about republican timing.
Bingo. The only problem is that the current timing of the leak is going to damage the report of the 9/11 commission. First we have the Wilson lie, which is apparently fully exposed in the 9/11 commission report, then we have the Berger document theft, which throws into doubt whether the commission had enough of the documents to make an accurate assessment of the pre 9/11 situation. When you combine the missing documents with the presence of other Clintonistas on the commission itself, you get a big fat zero for cheating.