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What if instead of launching Typhoon torwards Moscow in October, Hitler launched Guderian's 2nd Panzer group/army through Kursk, torward Voronezh to make an encirclment with AGS 1st panzer army.

3rd panzer army would provide flank support.

4th panzer army would remain up north to take and hold Tikvin and Voldolga to close the ring around Lake Ladoga.

The advantages seem to be that you deny/wreck as much of the black earth agricultural belt as possible to the Soviets before the end of the year, you can hold much of the Don as a defensive line and hopefully still hold Rostov at the start of next years campaign season.

Even without the advantage of hindsight encricling Moscow with its 4 million people and holding the ring until the city fell seemed beyond the reach of the Germans in 1941 but you still want to deny the production Donetz basin to the Soviets in 1941.
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