There's another, really rare aspect that this article didn't touch. In fact, it's so rare that I've only ever heard of it happening once.
There was a fan fiction writer, Melissa Good, who wrote a lot of Xena fan fiction. Robert Tapert, one of the executive producers of the show, contacted her and had her actually write 2 of the Season 6 episodes - Coming Home and Legacy. She was also to write a third episode that never came to be.
