Happy Homemade Sew Chic includes a lot of little errors. Most are not a big deal. Any competent sewist can use her better judgment and be fine.
But darn if the whole binding vs. facing issue doesn’t come back again and again. The book at times uses the terms interchangeably, but of course, aint so. It’s normally more of a style issue. If you want the edge treatment of the garment to show, use a binding. If not, use a facing. Easy peasy.
With the Tunic with Roll-up Sleeves, though, you won’t get the look you want unless you use a binding. If you follow the directions, you’ll be disappointed:
Notice how you’re told to do a facing, but you need a binding so that the neckline ties have someplace to go. I so read over the directions carefully, look over the pictures and use your judgment to get the look you want.