@Linkon:
Historically, Japan already beaten both Russia and China, often at starting battle odds of 1:2 or worse. They had local air supremacy, and often used combined arms tactics that were not avaible to the opposition.
I remember reading that their Siberia campaign stalled mainly due to bad weather that prevented their air power to assert.
Wikipedia reports that Tokyo put a limit on air attacks of Soviet airfields.
Later battles by Japan in WWII were typified by their numerical inferiorities.
I’m in the midst of working on a rules set for a WWII strategy game. Where possible, I have incorporated qualitative differences between unit types. For example, a jet fighter is much better at air-to-air combat, and a lot harder to shoot down, than a piston-driven fighter. (Though the difference between the best possible piston fighter and the worst possible jet fighter is rather small.)
I have been able to find some pretty good data comparing the qualitative effectiveness of German infantry against the infantry they faced. (Soviet, British, and American.) Unfortunately, my data on the relative effectiveness of Chinese and Japanese infantry is less complete. I have tentatively made Japanese infantry qualitatively the same as Soviet infantry. This means they are a step down from British or American infantry, and two steps down from German infantry. I have made Chinese infantry a step or two down from Japanese infantry.
Your post seems to suggest I may have underestimated the effectiveness of Japanese infantry. I’d be happy to have an excuse to strengthen the early game Axis, especially Japan. But before I can increase the qualitative effectiveness of Japan’s infantry, I will need a link to a reasonably authoritative source which addresses the subject of Japanese infantry’s effectiveness.