Interesting however, there is a line of thought that the Germans already had their jets in service before the British and Americans. Therefore the Germans had an advantage there. In addition they already were drawing up their next generation jets including one which looks suspiciously like a MiG-15. Don't forget also that the Soviets took one of the German Prototypes of this particular type, think it was the P.1008 or something away for analysis by their scientists. The Allies were very unwilling to deploy too much new equipment after WW2 and ended up getting surprised by the MiG-15 over Korea and Vietnam. It may have been a similar case in WW2 as well with the Allies constantly scrambling to keep up and counter the latest German fighters and bombers. Therefore we would have faced an Alice in Wonderland scenario where every time the Allies caught up the Germans may have moved the goal posts.