The way this "benefit" is implemented in the USA is that the funds are withdrawn directly from your linked bank account. In effect, you are able to use your American Express charge card as an ATM card. The withdrawal is slower than if you use a real ATM card issued by your bank, but you pay American Express a fee for accessing your own money.
This benefit is implemented differently in other countries, and the cash is actually added to the American Express balance.
Thanks for moving the post
Hmmm, interesting. I actually don't have my accounts linked (I really try to have none of my accounts linked). I didn't apply for anything either.
This piece of mail just says:
"You are now eligable for cash access." and just proceeds to tell me: "Cash access is granted for the card account shown above", I can use my Amex wherever Interac is accepted, and then just stuff about my PIN.
Very crisp clean letter (the whole 8.5 x 11 page is very empty).