If this dude goes to Citi that is kind of trashy for him to do. Citi like you said has gone to 10% of their value and their slogan is "Citi never sleeps" but that's only because they are too busy spending the $300 billion from the feds they got and I wouldn't be able to sleep either if I had to spend that much it's a lot of work!
Amex has a way better image and prestige than Citi. This Ken guy needs to stay right where he is.
If he does go then Fuzz you need to go work your way up at Amex and then take Ken's place. You are both lawyers so why not?