Good idea...
dasreich, you're theory is a good one, but I do see one issue- Speer didn't have anything to do with researching and testing new weapons; only production. And, early in the war, german equipment was not so much superior to that of the allies. The T-34 vs. early PzIV is a good example- the PzIV was up-gunned as a direct result of experience with the T-34. In other words, the germans did not create new equipment until they needed it. And even if Speer had been in charge of production, for the most part there was no apparent need for too much new equipment early on.
That being said, I do think the battle of Britian could have been greatly effected. Better planes with larger fule capacity could have allowed further penetration into England and longer missions. Better fighters could also have done much to counter the Spitfire. Possibly, the germans could have gotten Enlgand to sue for peace... but then again, that would likely cause the US to increase the support they gave England.

Good topic!

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