[Spoilers AGOT] Jaime Lannister as Warden of the East? - AGOT, Eddard II
"Kingslayer," Ned said. The rumors were true, then. He rode on dangerous ground now, he knew. "An able and courageous man, no doubt," he said carefully, "but his father is Warden of the West, Robert. In time Ser Jaime will succeed to that honor. No one man should hold both East and West." He left unsaid his real concern; that the appointment would put half the armies of the realm into the hands of Lannisters." - AGOT, Eddard II (Page 100)
Does this not contradict the fact that Kingsguard can inherit no titles, as Jaime would be inheriting the Warden of the West going against the oath that Barristan details in AGOT, Sansa V - ""I was chosen for the White Swords in my twenty-third year. It was all I had ever dreamed, from the moment I first took sword in hand. I gave up all claim to my ancestral keep."
This could just be an idea that was altered as the narrative went on but I am interested to hear what people think.