From what I understand, tracing them is also hard because (generally) there isn't any annotation on the blockchain to indicate who actually had them or what the

From what I understand, tracing them is also hard because (generally) there isn't any annotation on the blockchain to indicate who actually had them or what they were used for. So its hard to tell what point is just another place they laundered them, or someone who just got them in a transactions and then reused them elsewhere. Let's assume eventually they will be 'spent' somewhere- its going to be damn near impossible to track them down unless they transfer all of them into a single wallet with their name/address in the comment.