The Wardie cardigan is worked in pieces from the bottom up. When the front and back are complete they're joined at the shoulders and then the sleeves are worked from stitches picked up around the armhole. The shoulders are shaped at the back, with neat cabled decreases and the bound off edge of the front pieces wraps over the shoulder to join the decreased edge. This style of shaping is known as English tailoring and gives a beautiful fit and a neat finish that's often found on high end ready to wear knitwear.
If you're interested in knitting Wardie but aren't sure about the finishing here's how the shoulders and sleeve go together.