I have little doubt that if Hitler simply stepped back and said win the war and let his Generals have a free hand they would have done so. The German forces amoung other things had a very interesting command structure. There officers received very broad orders, and much was left up to them to decide in the field. This is why they were able to exploit favorable events so quickly, also high command lead from the front and was very often right behind the forward most units. So decisions could be made on the spot at a very high level. They were also masters at putting together "battle groups" from whatever units they had around.
I agree that the German General Staff, and senior commanders were some of the best ever collected together with a single military Concept, brought to the German Army by "Panzer Heinz", Guderian.
Constant training and commitment to a minimum of paper work. Most of this was all brought on by the German Army restrictions foisted on them by the settlements after the first World War. They found a way, and created at that time an efficient and effective force. The problem was the madman that got hold of that force.
The General Staff was not that happy about attacking the Soviet Union. Two front war, Operation Barbarossa started to late in the year, not enough oil reserves, net enough equipment, no winter gear, etc........ And of course the size of the USSR. That is what happens when you work for a madman.
The fact the Wehrmacht was as effective as they were given their defacto state of mechanization or under mechanization is a reflection of superior leadership, superior training, and great Esprit'. But the math of war was against them from the beginning, thank goodness. The fact is the great modern Wehrmacht moved by horse back. Even in the beginning. They never had enough trucks, let alone, tanks, guns, or even aircraft or fuel.
The British were never defeated or neutralized. 6 months later they were at War with America, and Japan had offered nothing to help the Germans in the Eastern Soviet Union. Hitler did not get any commitment from Japan to help alleviate some pressure off the German Eastern front by attacking in the far Eastern Soviet Union. The War math kept getting worse and worse.
And with very notable and very rare exception, War math always wins. (some folks like the term Logistics I prefer "War Math".)
SIDE NOTE: If you are reading many of the Panzer officers books and stories of the Russian front, one thing I have always found fascinating. They needed more tracked vehicles, not just half tracks either. At times they had to use Tanks as prime movers. I do know the Canadians recently have had to relearn that lesson in Afghanistan, AGAIN. Our brand new shiny Strykers don't work so well in A-Stan either. Iraq was a developed enough country that wheeled fighting vehicles worked and were viable. As soon as the terrain goes to hell, full tracks is what is needed. Some things never change.
Also recommended reading, Field Marshal Erwin Rommel's book, "ATTACKS!" Arguably the finest small unit infantry leaders manuel ever written. (Yea, written before he learned about driving tanks)
Sorry for straying off subject.
Go figure.
Fred