Suppose the Germans make the decision to use gas or a coal dust based weapons against the Soviets in early '43. Do the Soviets have the ability to counterattack? Will their use allow the Germans to hold off, or even push back the Soviet steamroller? And what of the Western Allies? Would they retaliate against Germany for their use? Perhaps they attempt a cross-channel invasion a year early? Discuss.
Note, I have two seperate scenarios in mind here:
1. The Germans use such weapons solely against the Soviets in the east.
2. They start out using them in the east, but decide to teach the Western Allies the same lesson, perhaps in Africa, or Italy.