The organization of training in the German Army had a threefold purpose; namely to relieve the Field Army of this task; to simulate, as closely as possible, the actual conditions of the battlefield; and to constantly introduce the most recent combat experiences into training practice.
To achieve the latter two of these aims, very great emphasis was laid on maintaining close connections between the army's two parts: not only were officers constantly being rotated between front-line duty and training units, but each of the latter was in addition tied to one or more divisions. Officers of the training unit and its parent division were expected to know each other personally and to exchange frequent visits and correspondence. Often it was recently wounded personnel, recovering from their wounds, who trained the replacements of their own division.
Well, except for the wounding part. Perhaps you could substitute "maternity" there.
The U.S. Army, by contrast put technical and administrative efficiency at the head of its list of priorities, disregarded other considerations, and produced a system that possessed a strong inherent tendency to turn men into nervous wrecks.
That's just how we roll.