This cardigan is worked in pieces from the bottom up with raglan shaping. The tucked rib is worked for 12 inches because the are no front bands to pick up or buttonholes to make. The stitches are allowed to roll under along the fronts and around the neck. The extra ribbing helps the bottom of the sweater to lay flatter. There is short row shaping above the ribbing on both back and fronts which help the sweater curve around your body - no riding up in the back. You can eliminate this shaping if it scares you (but really you can do it). If you can find the Peruvian Tweed, it’s worth it. The sweater is very light yet warm. I can order it for you if you can’t find it.