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A) the battle of Moscow happened after the release of troops from the central effort to focus on the Caucuses and Leningrad allowed the Soviets to reform their army, meaning they had been given time they normally wouldn't have had
Time was earned on the back of 4 million body-bags (includes the POWs). The RKKA was estimated as having just 200 divisions or less at the start of the campaign, by end of July some 180 had been destroyed and a further 180 had been detected mobilising using the "ECHELON" mobilisation set-up of the RKKA. By the end of 1941, the RKKA would have fielded over 500 division equivalents. Nothing in the world had prepared the Wehrmacht to fight such a gargantuan amount of men & material.
Again even in late November 1941, with 1/3rd of the Industry on Railway box-cars being transported to the Far East, the Russians were producing 800-900 tanks per month including vastly better T-34 and KV series Tanks. by mid-late 1942 they would be producing 2000 per month. German Tank production in 1941 was a measly 3500.
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B) the Battle of Moscow does not refer to just a battle in front of Moscow, but in fact the entire front. So of course it has a huge number of men on each side. However, the Russians were not, in fact, a cohesive fighting force at this point, as compared to the Germans. They were buying time desperately until the winter and logistical supply train of the Germans caught up with them. They were literally throwing men into losing battles for the sole purpose of buying time. They slowed down the German advance.
So? It is war and everything is fair in War. It was a WAR greater than any war before or since and all tactics are fair if it helps you win.
Again, the Germans never were a cohesive force like in June-August when fighting in November and December.
Gen Eduard Wagner, the Quarter Master General of the Wehrmacht and a man who knew infinitely more about logistics than me or you said this on -
27 November 1941 he reported that "We are at the end of our resources in both personnel and material. We are about to be confronted with the dangers of deep winter."
This shows, he did not believe his forces resembled a coherent enough force.
David Glantz in his book calls the RKKA and WEHRMACHT as 2 badly bruised boxers at the end of their strength in November 1941.
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The time bought, however, allowed the rest of the Red Army, including the Siberian divisions that were on alert for possible Japanese attacks, that when they never came allowed Stalin to focus his entire forces on the front against Germany. So in fact if anyone is to take the majority of the blame for the German loss, I would say it would be the Japanese who did not launch their own offensive (whether that particular offensive could succeed or not considering all the fighting they were doing in China is another story, but all it had to do was hold the divisions in place) as part of the Anti-Comintern Pact.
Siberian Divisions is a myth that dies hard, anyway the fact is that the Army of East numbered 750000 in May 1941 and in December 1941 it was over 700000 strong in number, shows hardly a decrease in numbers. What Stalin did is he pulled out his experienced troops and replaced them with raw recruits.
As for the Japanese, they got a bloody nose at Khalkin Gol-
https://en.wikipedia.org/wiki/Battles_of_Khalkhin_Gol
This decided their decision to go south and was reported by Richard Sorge to Stalin in September 1941.