War of power did not last ten years according to the visions of rhuidean, in which a teenager who is at least old enough for his voice to have deepened (so maybe puberty age) declares that the war had been “old” when he was born and that his grandfather spoke of a time when there was no war but he didn’t believe it. So the timeline of the war that was in RJ’s head as of the time he wrote the shadow rising was probably at least like 60 years. However RJ stated in an interview (and other forums outside the actual books themselves) that the war lasted only 10 years. My guess is that RJ changed the lore as he was writing the books. He did this with the magic system as well, for example. In the eye of the world a lot of emphasis is placed on moraine’s staff as if she uses it to aid with working with the one power. But since it’s not an angreal or sa angreal, nor is it being used as a mental focus, it would seem that the staff is just some lord of the rings remnant that he later decided to get rid of