Most of the topics in this thread revolve around Technology. How about looking at 'What If' from the doctrines of the various belligerents. I came across an article recently in which the author stated that while totals in flight time were not that far apart, total time in type would be completely different. As an example, a Japanese and American pilot might each have a total 600 hours. This author argued that the IJA/IJN pilots time would be in a specific type, fighter, bomber or torpedo aircraft while the American would have his time divided among all two or three types. Did other nations follow the Japanese or the American Models? What if US pilots trained only or mostly in one type?