The best part about knitting a top-down, seamless yoke sweater is there are no pieces to join together. Although, the prospect of picking up the sleeve stitches at the underarm may initially feel more intimidating than the thought of joining pieces.
As you are picking up the underarm stitches, it's important to pay close attention to the corners, at each side of the sleeve, between the held sleeve stitches (from the yoke) and the picked up stitches. It's really easy to get unsightly gaps there.
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