But in the spirit of this thread it has to be said that those 73 Divisions (49 Infantry, 20 Armoured and 4 Paratrooper) that Ike commanded in 1945 were division for division stronger in terms of manpower, vehicles, AFVs and guns than their Soviet and German equivilents. So each one could have more effectviely covered a greater frontage than the equivilent German or Soviet unit.
Hard to argue there. Just counting cannon, armored vehicles, and infantry weapons a 'average' Commonwealth corps had some serious advantages. Factor in the efficiencies from communication, much larger ammunition supply, fewer obsolescent weapons, ect... & the difference grows & grows.
Another issue is the connection between doctrines and logistics. US and British doctrines had their focus on firepower rather than manoeuvre. This probably reduced British and US casualties but also meant that a British or US Division typically required close to double the amount of supplies (mainly arty ammo) in combat compared to a German. ...
I've found it useful to use the measurement of the US/Commonwealth logisticians of 1944. That is "Division Slice" As applied to logistics planning & execution of Op OVERLORD it included all ground forces both combat & service, and tactical air forces ashore in Europe. This was divided by the number of division HQ ashore & came out to a standard of 44,000 men. To keep each division slice in sustained offensive combat the Overlord planners aimed at 900 short tons daily for each. This included a small allowance for a small reserve. From D +60 the goal was 950 tons rail to accelerate build up of a supply reserve in Europe. Source: Ruppenthals 'Logistics in Overlord".
It must also be understood the Logistics planners, & the Allied leaders from SHAEF through Army Group & downwards did not expect every division to be in offensive combat at all times. They anticipated that after a few weeks some 20%+ of the ground combat forces would be out of the battle zone to rest, repair, and train replacements. Much the same as the ground forces in the Pacifc, or the Mediterranean theaters.
I've only applied this Division Slice approach to a few brief back of the envelope calculations for German forces in western Europe. One of the points that jumped up in doing this was the paucity of tactical air forces to draw on the aggregate supply. Another was how to count the laborers in the Todt organization. A large portion of those performed tasks that were done by uniformed men in the US and Commonwealth service units. Unfortunatly its not easy to estimate how many should be included in the calculation for German forces and how many would be the equivalent of the European laborers employed by the Allied armies.
I seriously doubt if you, even with the US resources could keep 200 Divisions supplied in the OTL firepower doctrine on a Eastern Front infrastructure....
They'd have built their own infrastructure. The Persian Railway is a obvious example. Aside from completely rebuilding the railroad end to end they added to it, improved the port at the Gulf end, added a barge port at the north end, built a truck assembly plant, & miscl support facilities. Another example would be the US railways. Depending on the source & method of calculation between 70% & 120% of the railroads were reconstructed to modern standards & the capacity raised. Smaller examples would be the reconstruction or selected Italian railroads, a broader reconstruction of the Franco/Belgian railways 1944-46 from US provided material & financing. Given the same starting points as the Germans the Commonwealth and US were capable of rebuilding the core trunk lines and selected secondaries across the USSR as needed. Add in port construction capability & the capability grows.
The other half of the above is the question of 200 Commonwealth & US divisions being necessary.