In Ribbing Cast On, the number of Double Knitting rows may be one or two. Why is there such a difference?
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When making a Ribbing Cast On with One knit stitch on both ends, Double Knitting is only required in one row.
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When making a Ribbing Cast On with 2 knit stitches on the right end and 1 knit stitch on the left end, or a Cast On of a 2x2 Rib, Double Knitting requires 2 rows.
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If Double Knitting is knitted in two stages to create a circular structure, the knit and purl of the end stitch can be switched.
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