The Germans had something like this called Case Yellow in 1940. The was a plan to push the Allied forces back through central Belgium to the Somme river, in northern France, with similarities to the 1914 campaign of the First World War. But this was changed when the Germans were to strike through the Ardennes then swinging to the coast cutting off all retreating Allied forces. This is called the sickelstroke. The Ardennes Forest Front had the worst equipped and worst training in the French Army. The French thought that an army could not go through the Ardennes.The Germans knew that it was weakly manned and they took advantage of it.