Its also complete ridiculous that the french would throw in the towel in 1918 when the US had joined the war and Germany was on its last legs and would have spent their last drop of blood just reaching the channel ports.
It's hard to know if the French would really crack, even if virtually everything goes right for the Germans. By 1918, they're really bleeding out on the homefront with the aftershocks of the Turnip Winter and the continuing strangulation of the British Blockade. A successful Kaiserschlacht could buy the Germans a few more months.
From what I remember one of the reasons the Spring Offensive failed was that when the German Army overran Allies supply depots the ordinary soldiers abandoned their discipline in order to loot them and get something decent to eat and boots that weren't made of cardboard. This in turn led to a collapse of moral when those troops realised that unlike what they'd been told the Entente nations weren't enduring even worse hardships than Germany. Even if the Germans somehow reached the Channel ports these things aren't going to change and may get worse with the Germans capturing civilian areas as well as military depots.
The mass casualties would be equally present with a successful Spring offensive. Going on the offensive on the Western Front in WW1 was costly, no matter who did it or how. Even if the Germans (somehow) manage to push the British back and take the rail depots, the German army will be a much reduced force afterwards.
For sure, reminds me of when in the latest rendition of All Quiet on the Western Front the Germans start devouring left behind French rations in the middle of a firefight.
Oh of course, defeat is still likely even if all goes to plan. A decent deal of damage on the BEF and French Army may buy some time as they sit and recover, but I see few opportunities in 1918 for the Germans to pull something out of the bag that slightly resembles a victory.
What does it actually get Germany though. A few months extra, another winter made worse by the British blockade and Germany's allies collapsing in Autumn and complete defeat in the face of the Allies spring 1919 offensive with millions of fresh US troops added to the experienced Anglo-French and an overwhelming technological superiority.
Very likely, best case, the Allies to recover from this successful German offensive pull a few (more) divisions out of Italy, Salonika and Palestine, as well as delaying their own counter offensive until 1919. Maybe if the Germans take the Bethune coal mines, coal has to be imported from the USA to replace the lost French sources delaying the Allied build up.
"This is not Peace. It is an Armistice for ten years."
Almost every government acted duplicitously. Especially among the major powers. This wasn't unique to the Germans.
I remember seeing a documentary on WWI where an excerpt from a Uboat commanders memoirs are read in which he explains when he realised the war was lost,
I recall one I read where a German officer during Michael setting up in a British dugout they had overrun noticed that the floor had been made level through the use of 'in date' cans of bully beef.
Which will be answered with 'Le get bent' by the massive french army still in the field by 1918, the toppling of the pacifist government that even considers accepting this demand for mass french starving especially as the germans only just barely reached the channel ports in this PoD, and a immediate resumption of hostilities and ending with Germany collapsing finally in 1919 from the blockade.
Well it was an armistice of 20 years OTL, so yes maybe, or maybe not, but Britain has about the same level of improved security here, no German colonies, no world wide submarine bases, red sea and Persian gulf have no strong enemy states on them to contest their control.
