They did in the field. Problem seems to be that these ad hoc units were then immediately committed to battle and often destroyed in the process.

The German infantry units in the West suffered the same horrendous attrition as the Allies, with one telling difference. The 30-day and later in early 1944 60-day rule of keeping those in hospital on company books greatly exaggerated strength, while assigning replacements 30 days after requisitions were submitted kept the units undermanned even after the requisitions were filled. Thus, the German replacement policy detracted from rather than enhanced German combat effectiveness. Once committed to combat, a company never again reached full daily strength unless pulled from the line for an extended period. Consequently, amalgamation of combat units and stripping of non-infantry trained support organizations had to occur for units to continue to exist, as did happen.

http://i.imgur.com/rc4Y4xN.png

In fall 1944, only select German divisions were pulled out to reconstitute and most infantry units remained in the line during combat until they were bled dry; maintaining strength primarily through absorption of smaller units. Commanders repeatedly consolidated decimated units, with each consolidation lessening units’ organizational coherence, until their ever-dwindling bands of soldiers disappeared forever: killed, wounded, captured, or surrendered. With combat power gone, the commanders, staffs and certain specialists returned to build a new unit, while those few men remaining on the line in subordinate organizations were absorbed by newly arrived headquarters.

If the U.S. Army had used the German replacement rules of keeping wounded in hospital on its books for 60 days. U.S. rifle companies would have required around 247 “actual strength” soldiers to maintain a daily average of 157 soldiers. The American system of dropping soldiers from the rolls of rifle companies when they were evacuated beyond the division rear areas and their subsequent re-assignment upon convalescence worked best--keeping units nominally up to strength while ensuring that veterans returned where they were most needed and most wanted.

...During its battle in the woods, the 22d Infantry fought elements of thirteen German regiments. Only the regiments of the 275th Infanterie Division had any success against the Americans in the Hürtgen forest, principally because they had been in the Grosshau area since early October and their commanders knew the ground. The 275th entered heavy combat against the U.S. 28th Infantry Division in October 1944 and the 4th Division in mid-November. This German Division was bled dry after just four days of intense fighting against the 4th, and the 275th relinquished battle control to the newly arriving 344th Volksgrenadier Division, which absorbed the combat elements of the 275th.

Quickly decimated, the 344th controlled the battle for just five days of fighting before transferring command of the battle around Grosshau to the arriving 353d Volksgrenandier Division.

Four days later, the 353d was an amalgam of disparate units holding a tenuous line of small towns that prevented movement into the Rur River plain. When the 22d seized Grosshau on 29 November, the German units were so such a mixed bag that the 133 Germans captured near Grosshau were from 15 different companies, 6 different regiments, and 4 different divisions. Later regiments from yet another division acted as a counterattack force in attempts to throw the Americans back.

http://i.imgur.com/8UgYZtk.png

In contrast to the American Army in the Hürtgen Forest, the German Army allowed units in contact to wither, and instead of reinforcing these veteran organizations, consolidated them when they grew too small; while committing newly rebuilt units of relatively fresh but untried and untrained men — to little avail. German companies suffered the same fate as the 22d’s, but lacked the ability to regenerate and disappeared as organizations in the Hürtgen. 26 When the final phase of the battle for the Hürtgen Forest ended in early December 1944, it was the Americans who had gained the ground and the Germans who had had to surrender it — in a battle where much-mentioned American superiority in air support and logistics went for naught, and artillery was equally available.

Twelve days after its relief from the Hürtgen Forest, an exhausted and debilitated 22d Infantry was reconstituting in the quiet sector just north of Luxembourg City, with companies of 50-60 soldiers holding 5,000 yards of front. There, they were struck by elements of the 212 th Volksgrenadier Division during the opening phases of the German Ardennes Counteroffensive. The 212th was experienced through hard service in Russia and had been reconstituting since late September 1944 for its role in the Ardennes Campaign. In January 1945, the Ia (Chief of Staff) wrote about the first seven days of the battle.

Company leaders were not experienced to fight in the West and lacked terrain appreciation as well as underestimated the fighting abilities of the Americans.

The biggest problem was the 20km front — this tactic only works if the enemy is flank sensitive and surrenders strong points when bypassed, but in reality the American strongpoints offered grim resistance even when the situation appeared hopeless.

The enemy was tenacious and showed strong resistance. The key to the success of all American attacks was, besides the material superiority, the outstanding training of the individual soldier and, in particular, the fire discipline that was evident everywhere.

Infantry wise, through the steady flow of replacements of fresh, rested forces the Americans slowly achieved the upper hand against our own troops, which were severely weakened by deprivations and exhaustion for days, so that even instantaneously launched counter attacks did not succeed from the 7th day of battle onward.

The main weakness of our own leadership lies in the insufficient experience of company leaders for such an extensive battle. They were not capable of leading their companies in this environment. … This was the division’s [212 th ] first experience against the enemy in the West. 27

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