I recall a colleague in the mid Eighties who used to claim that he booked two tickets, one refundable in First, one in Coach. He'd print off both sets of boarding passes, check in using the coach ticket and board using the First BP. Upon return he'd refund the First ticket. He claimed to do this by omitting the space present in his surname pn one booking which led to his two personae being greatly spaced on the manifest.

I have no clue if he was just winding up a young and impressionable Deckard.