lol yep yorkies are smart and she is pulling a fast one on you for sure. My girls use to do that to me. When i would give them treats after they went potty. I might just give them lots of praise when she really goes. Check to see if it is wet and she for sure went before you praise her or give her a treat. Another way to check is lift her up and see if the hair around her girl part is wet. She will soon learn that you cant fool mommy.
