Now, hypothetically what would the greater effects of Entente forces being completely routed on both fronts, other then Italy and Greece exiting the war possibly.
Italy exiting the war would become neutral, rather than swap sides, and whilst its industry would be at the disposal of the Central Powers (by treaty) there won't be transition of troops or a new front in the Alps
Greece on the other hand would probably see a royalist coup and enter the Central Powers side of the war
You HAVE TO factor in the blow to Allied morale and the lift to Central Powers morale. Italy going out will make it seem to the people of France and Britain that a general collapse may be only so far off. Industrial unrest, strikes, etc would rise
Beset Rearguards
Grey Wolf