The charge of Charlemagne's infantry was hell for them and a nightmare for the Wehrmacht as well.
Unlike the tangible injuries and deaths Charlemagne's infantry was subjected to, the pressure on the Wehrmacht primarily stemmed from psychological distress. It is worth noting that in the first hour of combat after the offensive commenced, Charlemagne committed a staggering 66,000 men. The Wehrmacht soldiers in the frontline fortifications were about a third of the enemy's strength, and their most effective artillery, engaged in slaughtering Charlemagne's comrades, could not spare the time. Otherwise, not even double the current enemy numbers would have been considered a threat.
Since they relied on the artillery brothers, all they could depend on were their weapons in hand, their repeatedly honed skills, the comrades at their sides, and their own will.
"1500 rounds! Change the barrel!!"
