By Mark Wallace
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It's obviously important to establish properly agreed spending plans for each department through the Coalition's full term in office. But there's also a hefty political element on the Chancellor's part - as can be seen by the chaos it has thrown the two Eds into, unable to decide whether they'll spend and borrow less, spend and borrow more or insist that both are possible.
That political motivation is also true of some of the Cabinet. It is telling that Vince Cable was the last one to agree a deal with the Treasury, and the very public manner in which he did it. James Forsyth of the Spectator was not alone in being briefed that the talks would last late into the night on Tuesday (though in practice they ended late yesterday).