Hi, Steve!
I never said that the moral in 1918 was good, it was acceptable. There were problems because of the blockade and there was alot simmering under the surface, but as long as there was hope for a victory, the moral held.
I know the british were fed up with the war, too, but I don´t know how down the barrel the BEF was. It can´t be too good, since any substancial reinforcements would have come from other fronts. But I agree, smashing the BEF would have been costly. Doable, but costly. In any case, the Heer would have pushed against the french lines. Several independent sources agree that France was spent worse than the CP. The german army might not be able to push much further, but France alone would have been unable to hold the lines.
As I wrote, the foreign ministry was not the disaster from earlier and knew, don´t push too far when the negociations come.