Our Gracie is a parti, so absolutely, but I am not sure about our first little one. Sometimes they would have several yorkies at the groomer's shop, and I would talk to her to see how she reacted before I was sure they were sending the right dog with me! To the groomers credit, though, I am sure they could tell the difference.
It reminds me of my mom and her sisters joking about hosing us off after a busy summer play date to make sure they took the right kids home.