Steinach advanced this claim from 1918 onward, publishing its theoretical basis in 1920 and popularizing it through the 1920s. The endpoints used were surrogate: patient self-report of energy, libido, and cognitive sharpness; surgeon observation of skin tone and gait; and rat behavioral proxies (restored sexual activity in aged animals). No controlled human trial compared vasoligation recipients with sham-operated or unoperated controls. No hard endpoints (mortality, objective function measures) were reported. The synthetic isolation of testosterone in 1935 revealed that circulating androgen levels could be measured directly; subsequent endocrinological work did not support the claim that vasoligation reliably elevated testosterone. The procedure was abandoned as synthetic androgens became available from 1935 onward. The claim is refuted: the mechanism was not demonstrated and the clinical effect, if any, is attributable to placebo and the unmasked surgical context.