"You can't negotiate with an idealistic immovable object"
Back in the day, I used to do a fair bit of negotiating. Nothing remotely on this scale of course, but it usually involved some pretty large sums of money.
Most of the time it seemed as if I was doing exactly what LastChip says you can't so - negotiating with immovable objects in the shape of Trades Unions.
In my experience, the resolution always seemed to appear in the very late stages of the process, just as the deadline was getting close. We all took it close to the wire, and then the process of compromise began.