Why would they emphasize this point? Why is this a central element in the movie? Not everyone is a slave to your biases, you know.

I just finished reading it a week ago, and as far I remember thats what was written. Shirer (or however you spell his name) also attributed most of the crucial mistakes to Hitler - to begin with, the decision to attack Yoguslavia at the spur of a moment, which delayed Barbarosa by a month, closer into the Russian winter. he mentions his command not to retreat under any circumstances as what made defending the german front impossible, his failure to attack moscow in time when it was possible, and generally many other decisions that seem arbitrary and against any military experience.