"If I remember correctly, Chaum's original paper didn't deal with offline double spending. It was blind signature based online e-cash that depend on the bank ke

"If I remember correctly, Chaum's original paper didn't deal with offline double spending. It was blind signature based online e-cash that depend on the bank keeping a list of spent serial numbers(which isn't much easier keeping an account balance). So it's point was mainly anonymity." The point was anonymity and the assurance that double spending is hard. Let's put it this way: how do you know that the attacker cannot create tokens that the bank did not issue, but that the bank will believe are valid? The point of Chaum's original system is that you can prevent such an attack and allow anonymous spending. If the only concern were anonymity, the system would not be hard to create: the bank would just accept everything and the spenders would just create random strings instead of using the withdrawal protocol.