It's not just an interesting idea - it's very much the norm in much of the banking industry in my neck of the woods. It's generally considered one of the best ways of picking up internal fraud.

One example that springs to mind from Australia was a branch staffer who had managed to rack up A$5 million dollars in fake mortgages. Went on holiday, the stand-in noticed dozens of mortgages to the same PO Box, did some digging...