Clever way to mark studs when remodeling - Painter's tape

We had a fellow doing some work and I noticed he was using painter's tape to mark studs. Very clever. More visible than pencil marks and doesn't require cleaning or painting over the marks. He put the painter's tape just outside where he was mounting the wood, so it would still be visible when he lifted it into place, and the smaller tape is almost exactly the same width as a 2x4, so it can be used to mark exactly where the edges of the stud are.