this, i would suggest, is where the yawning chasm between commercial negotiations and politics shows itself.
leaking a document and allowing the other side to note your populations deep displeasure over the contents of that document is a very good way of showing your opposite number what can and cannot be achieved - if your negotiator says 'thats not possible', your opposite number might believe that to be a negotiating position, if however he see's your opposition, media and electorate go up the wall he knows that no, its not possible and he stops wasting time barking up a dead tree and spends his time more productively barking up a live tree.