Ich bin wieder da! Let the fun begin.
The question is a simple one...pure economics and geopolitical reality. I have stated over and over again that the problem of mass is unimportant. Read any analysis of war principles. The issue of mass falls to that of effect. Concentrating a million men counts for nothing in relation to the concentration of a million bombs. War is a matter of effect.
Russia fell to German arms in WWI. WWII was not all that different a scenario. The Russians were beaten to a pulp. A look at the last major German "defensive" action of the war makes this point clearer than glass. The Germans, even in their dying hours, were able to kill Russians on a supreme scale -- the battle of the Seelower Höhen. Without a western European contribution, Russia was screwed, dead, nothing.
The following link is only for the purposes of the general public. If you want more or complain about wiki, then first prove that I am incorrect by way of source material. I can give enough to choke on. If you feel qualified to make a strong stance, please explain how.
http://en.wikipedia.org/wiki/Battle_...Seelow_Heights