The medical profession, and the government agencies that regulate it, are accustomed to risk and have systems to manage it. The problem is that classical medicine is tuned to "continuous risks." If the Risk of 100 mg of aspirin is "1 risk unit" and the risk of 200 mg of aspirin is "2 risk units" then the risk of 150 mg of aspirin is strongly likely to be between 1 and 2, and it definitely won't be 1,000,000. The mechanisms we use to regulate medicine, with dosing trials, and pharmacokinetic studies, and so forth are based on this assumption that both benefit and harm are continuous functions of prescribed dose, and the physician's job is to find the sweet spot between them.
When you let a computer handle a treatment you are exposed to a completely different kind of risk. Computers are inherently binary machines that we sometimes make simulate continuous functions. Because computers are binary, there is a potential for corner cases that expose erratic, and as this case shows, potentially fatal behavior. This is not new to computer science, but it is very foreign to medicine. Because of this, medicine has a built in blind spot in evaluating computer technology.
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