I actually don't believe the German generalship as a whole had the skill set to win this war. They could win battles, which was enough going up against Poland and France, but they didn't have the tools (or the skill set) to execute a Sea Lion nor to defeat Russia.
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It is a BBC documentary about design and design philosophy, but if you look at some of what they present it is also about war-making philosophy. How the allied priority was first and foremost to get the quantities needed to win, not just the quality.
I have same opinion about the need for quantity as well and I also think that the Germans made a mistake when they had
a) several organisations inside the military forces (for example: Wehrmacht, SS and Luftwaffe had all infantry forces).
b) they had several weapon projects, that indirectly hindered the Germans to get enough quantity.
But I think most of this had to do with Hitler and the Nazi ideology. Hitler had some kind of strange interest in different super-weapons, which looked cool for him on the paper, but which was completely useless on the battlefield (for example the Maus). But I don't think the German generals could influence this so much. It was Hitler who was the dictator. For example Guderian mentions this quantity problem in his memoirs, when he mentions about the production of tanks and tank-destroyers.
Hitler had also a great distrust in the German (mostly Prussian aristocratic) generals. Therefore he didn't listen to them and made instead his own decisions. Hitler chose Keitel as the leader for the Oberkommando der Wehrmacht, not because of his military skills, but because he would do exactly as Hitler wanted. At least the other general had this opinion at the time of Keitel's appointment and also later.
I do not believe that the German generals had so much power to influence Hitler in his decisions, either in military decisions or in production decisions. Therefore we don't know if "the German generalship as a whole had the skill set to win this war", because they didn't get the opportunity to show their skills.