I can't think of a reason why the designer did this but she probably had a reason. Whatever the reason was, I'm sure there is some way to get around it, if you really want to, and still get the same effect, or to choose a different effect.
Grafting is, I believe, the same as what many people call kitchener stitch, your books may have instructions under that name. If you search these terms on google, or search 'kitchener stitch tutorial' you should get lots of websites with detailed pictures and explanation on how to do it, tips to make it look good, etc.
If you find it confusing or can't understand it at all and can't get anyone at your local wool shop to show you, you may want to try another way, but I say try kitchener first.
Have a look for tutorials for grafting/kitchener, if you really can't do it, we'll be happy to help explain it or to offer suggestions on another way of doing that part. If you want another way to do this without grafting, post a description of the pattern preferably with a picture, and more of the pattern (or a link to it) if you can.