Devers was artillery. He was one of the men who modernized fire control at Ft. Sill, which paved the way for the devastating effectiveness of American artillery in WWII.
I can't figure out what the problem was leading to the Ike personality dispute. During the North Africa and Sicily campaigns, Devers replaced Ike as commander of the ETO, which at that time was just the British Isles. Maybe Ike thought he was trying to steal his command?
Marshall really liked Devers, so it seems a little odd that Ike took such a dislike to him.
Devers was in the running for SHAEF command. I think Ike saw him as a rival. Maybe it was nothing more than a personality conflict. There are guys I know who are generally well-liked but I personally can’t stand to be in the same room with them. And I know some guys who most people think are a$$holes but I get on with them all right.
It’s just how we’re put toghether.
Strange as it seems, from what I’ve read I think I would probably have gotten along reasonably well with both Monty and Patton, but would have had no use for Bradley.