[gogeek]

"Finally, teams with more women outperformed teams with more men. Indeed, it appeared that it was not “diversity” (having equal numbers of men and women) that mattered for a team’s intelligence, but simply having more women."

They explicitly claim "more women = better performace" and not adding one woman improves the male team's performance.

I assume this is highly dependend on the task and male teams make up for their weaknesses with other qualities in the long-term, like ambition and persistency.