What is interesting about this hypothesis is that it does not require men to be especially sexist or treat women poorly. Men only have to be a bit more assertiv

What is interesting about this hypothesis is that it does not require men to be especially sexist or treat women poorly. Men only have to be a bit more assertive, or better able to build coalitions among their colleagues, for this effect to occur. These factors, plus the general observation that women tend to score significantly higher than men on the Big 5 trait of Agreeableness, make this thesis plausible. I look forward to seeing it tested further. This study appears to focus on female engineers who have already passed at least some filters for aptitude/interest in engineering, so one would expect any possible effects of biological sex differences/average population differences to be less important to the results.