The header-right widget area was never actively part of the themes - just something kind of inherited from Genesis and left in. But over the years, it's proven to be extremely difficult to configure properly, and not all that useful.
And since we don't recommend it, we don't provide tutorials for it, which confuses people as to why it's there.
In version 4.1.5+ of the themes, it's been removed.
While we don't recommend it, you can add it back by uncommenting the following line form functions.php:
unregister_sidebar( 'header-right' );