Correct me if I'm wrong, but Ike wasn't a battlefield general. He was more like a big picture, logistics guy. Guys like Patton and Clark were the battlefield generals, the guys who needed to know how to fight.
You need the "big picture, logistics guy" for overall war planning. Even if he knows real battle tactics, he won't have the opportunity to use it.
After reading the Wiki write up on his career I would say that is an accurate assessment. He was not ordered to Europe until late in Great War, and never saw combat due to the armistice. He was admired for his "book learning" military strategies and administrative and organizational skills. He was a pogue.
