Nope, teaching boys (or anyone) that they have a role is incredibly harmful because there are a million ways to be a man and telling boys that there is one way drives many of them to despair - as boys and men themselves described in the story I already linked to you. But tons of research on the topic agrees. Telling someone who they ought to be is never helpful. Nurturing and nourishing them to be whoever they actually are is what is beneficial.

Nobody knows how to be a parent - even people who grew up with both parents don't know. And as noted in my OP, other factors like potential poverty, and not having 3 other secure adults may have been the real issue. I didn't say that all boys without dads in the home turn out just fine - I said that there is no actual evidence that not having that is an immediate indicator of dysfunction. In fact, only 23% of Americans are being raised by a male/female couple - are you actually purporting that the rest are all screwed?

How did George Washington, or Bill Clinton, or Barak Obama, or Michael Phelps (and millions of other boys) grow up just fine?