Informed consent: Is evidence of my habit enough?

Dr. A, like every other dermatologist, performs myriad skin biopsies during the course of her workweek. She explains to her patients in detail the purpose of the biopsy; the possible need for further treatment pending the biopsy results; and mentions that there may be a scar at the biopsy site. She gave this information before performing a curette biopsy on the face of a 25-year-old actress. In her chart notes Dr. A writes, "biopsy discussed in detail with patient." There is nothing in the chart documenting any discussed risk of scarring. No written consent form is obtained. Unfortunately, the biopsy