What Panzers did Panzer officers use? How did a Panzer unit attack, as in did the smallest tanks protect the sides of the big ones? Where would a Stug III fit into that, and where were the Panzer officers stationed in attacks (front or rear?)
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Panzer officers of larger units could use a command tak, with a dummy gun. (Tank had more room inside for extra radio gear with the gun removed.) The Germans developed the Panzerkeil armored wedge formation for large scale attacks. Stug was not considered a tank.
Some senior officers used a half-tracked vehicle with appropriate radio equipment as a command vehicle. Some of the contemporary pictures of Guderian show him in such a vehicle. Generally, most armies including the Heer, wanted the infantry to break through the front lines of the enemy and then use the armored units as exploitation forces. For this role the infantry divisions were issued the Stug III which started out just as an infantry support weapon but later in the war they were equipped with a high velocity gun and also did anti-armor work as well. While the Stug III was originally an infantry weapon, some were used by armored units when supplies of tanks weren't available to make up losses.