People are trying too hard to project the manpower shortages of mid 1918 into mid 1915. Simple arithmetic shows that 1915 Germany has no manpower shortage.

Stunned disbelief.... Dave please read some of the books that I have suggested. The First World War: Germany and Austria-Hungary 1914-1918 by Holger H. Herwig and Feldmen are two best books in English that you are going to find on the subject.

Germany went through cycles, at different points they went through having too much manpower but not enough material, balance and not enough manpower compared to material. Its not simple as saying Germany in 1915 had no manpower shortage, because they did but not in all areas. Its a question of resource managment really and the Germans, like everyone else, learned as they went. In 1915 they had a great deal to learn. The idea that just waving a magic wand will come up with the manpower (in particular skilled manpower), raw materials and production capacity to meet an expanded needs of the HSF and the army is just not realistic. Its a closed system, if you put in X that has to come from some place and the Landsturm are not a good source for it for reason I already explained.

Also Germany was not a highly centralized state, it was a federal state and in time of war it acquired 25 additional petite tyrants in the form of the Deputy Commanding Generals. THEY and not the War Ministry or the German Civilian Government had final say over what happened to manpower within their corps districts. Each was a law on to themselves with no real uniformity of conduct; Feldmen and to a lesser extent Herwig go into detail on the problems over manpower those Generals were.

Michael