AlvaStitcher--If you plan to do one continuous feather, I suggest you get a practice piece to work on and try those turns around the corners! I frankly find that when I do continuous feathers, to keep them consistent, I do the center part of the quilt first, then have to do the borders all at once--which means I'm doing a lot of rolling back and forth. For that reason I sometimes will do a motif in the center of all sides and the corners, then feather between.
Also, I find that when I have a stitched in spine, I tend to get the spines too "heavy"--so I'll mark a spine with chalk, then just start the feathers and go to end. then I break the thread and go back to the start and feather the other side--the way they lay together almost creates a "spine" but I don't get the thread build-up. A friend who does amazing feathers uses this method and while I still need a lot of practice, it sure works better for me.