Sharing Responsibilities

http://m.washingtonpost.com/news/morning-mix/wp/2014/07/07/children-of-same-sex-couples-are-happier-and-healthier-than-peers-research-shows/

I read this interesting article today.  Although there is plenty in it worth discussing, the item I'm picking out to discuss now is, "same-sex couples are likely to share responsibilities more equally than heterosexual ones".  I found that very interesting.  Would this be because of the existing stereotypical roles assigned to male and female, so that when there is one of each, the breakdown in responsibility more easily falls in line with those roles?  And then when there is the absence of that traditional definition of a gender role, when it's 2 females and no males, or 2 males and no females, the traditional roles aren't so easily applied?  We used to say things like, "she wears the pants", and "she is the man in the relationship", and so forth.  Perhaps homosexual couples really do not break into stereotypical roles like some of us thought.  Perhaps it is a truly more equal division of responsibilities, more gender neutral.