revision preference src: Although ultimately discounting brain surgery as carrying too much risk, physicians and neurologists such as William Mayo, Thierry de Martel, Richard Brickner, and Leo Davidoff had, before 1935, entertained the proposition. <SEP> tgt: Ultimately discounting brain surgery as carrying too much risk. Physicians and neurologists such as William Mayo, Thierry de Martel, Richard Brickner, and Leo Davidoff had, before 1935, entertained the proposition.