I assume that the Vokssturm units can stack with two other units??
For instance in Koningsberg in 1945:
1st Fetsung unit
volkssturm koningsberg unit
Reason: The volkssturm unit were in reality a very small 'unit' of mainly citizens who were already there!
Maybe Carl can shine a light?
By the way: 3th edition is a wonderful game
Thanks for the kind words!
Sorry but no, you can't stack the Volkssturm units extra, maximum is 2 units per hex. You are right with your historical assessment, but in my "design for effect" that extra stacking is not allowed to represent the general degradation of the German operational tactics because of lower troop experience and Hitler's senseless orders. The units also does represent some "bottom of the Drawer" German Army units scratch token forces (rear area, supply, navy troops etc.).
Mind you, feel free to try it as an optional rule and let us know how it went (I tried it when making the game and it was not a success, made the Germans able to hold their line in German unrealistically long).