Debating a testosterone "sex gap"

Sex dimorphism of testosterone (T) in elite athletes was at the center of a recent case at the "Supreme Court of Sport", the Court of Arbitration for Sport in Switzerland, after teenage Indian sprinter Dutee Chand challenged a sports policy regulating competition eligibility of women with naturally high T. The idea of a "sex gap" in T is a cornerstone of this policy (1). Policymakers infer that men's higher T is the "one factor [that] makes a decisive difference" between men's and women's athletic performances (2) —so they claim that women with naturally high T unfairly enjoy a "massive androgenic advantage" over other women athletes (2). Yet there's an emerging scientific debate about whether the sex gap in T applies to elite athletes.