Whenever I hand a taxi driver a slip of paper with an address written on it, they invariably flip the paper over and study whatever scribbling is on the other side. It could be Granny's recipe for fruit cake, it doesn't matter, they're determined to figure it out. I tell them to flip the paper back and only look at that address. They glance at it, then flip over the paper and continue studying the back again. It's easier just to make sure nothing is written on the opposite side of the address.