Findings reveal all-male units outperformed mixed-gender unit but Navy secretary says study was flawed because of mindset of volunteers A US marine corps study examining how women would perform in ground combat roles showed all-male units broadly outperformed mixed-gender units on everything from reaching targets quickly to firing accurately with heavier weapons. The results of the study, a summary of which was released by the marine corps this week, could factor into Pentagon deliberations about which roles, if any, should remain off-limits to women. The US military services will soon submit their recommendations to Defense Secretary Ash Carter on the...