This is so timely and important a topic!  I am interviewing corporate sustainability leaders right now for some academic work (which will eventually be shared in some way outside of my master's degree, I'm sure).  I am specifically only talking with men, because I am interested to see whether so-called gendered leadership styles emerge.  So far, it looks to me as though the best leaders are those who have that pragmatic/"hard" side well-covered but who know that also tending to the "soft" side will exponentially improve their leadership persuasiveness/effectiveness.  Especially for sustainability-motivated organizations today, diversity and a willingness to just finally get over this "hard" vs "soft" idea will be key.  If we stop talking about it as though "hard" and "soft" skills are polarized and connected with specific genders - we'll open up a whole new conversation.  Great piece - thanks for writing it up!