Legally and ethically physicians must provide information to patients so they may make an informed decision about invasive procedures. The problem is who decides what information to provide. Is it the reasonable patient or the reasonable physician? Individual patients and individual physicians may differ from the norm on what is reasonable. This problem may be solved by shared decision-making in which the preferences of the patient and the probability-based knowledge of the physician are used to co-produce an optimal choice. Currently, patients are seldom prepared to engage in shared decision-making, and vestiges of meaningless "informed consent" are common. The present case study illustrates how "reasonable person" survey data may be used by a patient to engage in probability-based, shared decision-making with a surgeon planning to perform a laminectomy. Recommendations include probability-based, shared decision-making training for patients and physicians and improved documentation to facilitate learning.