What's the Value of Gender Diversity, Anyway?

Uber is reeling due to a series of damning reports about it's corporate culture of misogyny. One potential solution that makes impact investors ears perk up: diversify the board. But, a new study from Katherine Klein of the Wharton School suggests that "the relationship between board gender diversity and company performance is either non-exist (effectively zero) or weakly positive." How do the findings effect the conversation around gender lens investing?