Interesting write-up on how to disable RFID that is built into most credit cards these days as part of the “tap and pay” method. Why would you do this, well to keep thieves from wirelessly scanning your wallet of course. My only issue is you are assuming the antenna always goes around the edge of the card when you “cut” it. I guess if you have an RFID reader you could test if its cut off.
http://www.instructables.com/id/Disabling-Contacless-Payment-on-Debit-Cards/