Darren: Did Arthur Friedberg get back to you on if the serial numbers on bills were recorded right before they were destroyed? At about 8:33 into the podcast he says he does not know if the Treasury does that. He actually says that a couple of times. He offers to get with the BEP (Bureau of Engraving and Printing) to confirm. I know RB has had some contact with someone who works there and they say that serial numbers were not recorded.
I just listened to the podcast again. I thought he was a great guest, and is clearly an expert on money. However, he states a few times that he really does not know much about the Cooper case. His theory hinges on the money being in as bad condition as the Ingram bills, and therefore these would raise a flag if they were spent.
Not knowing if the BEP/Mint/Treasury etc. records serial numbers seems to create a gap. He thinks the money would have shown up, but I did not hear any logic as to how someone would have actually found the bills, except when he mentions them being spent in huge lots.
I've talked to some money experts, and find them to be very useful in terms of things such as how many of each denomination were produced, how long money stays in circulation, where money could have been spent outside of the US, etc. However, you can be an expert in money, but that still does not mean that people were looking hard for these bills.
I took some notes and can respond more at some point, but I'm mainly curious as to what he says about the serial numbers being recorded.