True, I remember one study (I can't recall the link sadly) that measured performance of several programming teams and found strong correlation between women in workforce and team performance.
Another study in the book "Imagine" by Lehrer Jonah implies that creativity depends on the Q factor, inside a group. Here is a quote:
"Uzzi’s data clearly demonstrates that the best Broadway shows were produced with intermediate levels of social intimacy. A musical produced at the ideal level of Q (2.6) was two and a half times more likely to be a commercial success than a musical produced with a low Q (<1.4) or a high Q (>3.2). It was also three times more likely to be lauded by the critics."
I can see how hiring only rockstars which probably knew each other would increase the Q beyond the ideal level.
Another study in the book "Imagine" by Lehrer Jonah implies that creativity depends on the Q factor, inside a group. Here is a quote: "Uzzi’s data clearly demonstrates that the best Broadway shows were produced with intermediate levels of social intimacy. A musical produced at the ideal level of Q (2.6) was two and a half times more likely to be a commercial success than a musical produced with a low Q (<1.4) or a high Q (>3.2). It was also three times more likely to be lauded by the critics."
I can see how hiring only rockstars which probably knew each other would increase the Q beyond the ideal level.