I agree with.

Unlike Hitler, Guderian and Von Bock were not politicians. Brilliant commanders, but not politicians. It may seem that they were simply unaware of how vital Ukraine was to the German cause in the East while Hitler did. Guderian and Von Bock both believed that capturing Moscow was the end of the war. As we know now, there is more evidence to contradict their assumptions then support them.

Here is a question which David Glantz asks,

If the Germans had such a hard time defending their flanks against the Red Army numbering 4.1 million men and reletively short supply lines, then how might they fair against a Red Army numbering 5 million men and even longer supply lines?

__________________
The war against Russia will be such that it cannot be conducted in a knightly fashion. This struggle is one of ideologies and racial differences and will have to be conducted with unprecedented, unmerciful and unrelenting harshness. -Adolf Hitler