lace butterfly knit stitch

This is an attempt to reverse engineer the stitch in the swatch at https://www.knittingkingdom.com/lace-butterfly-knit-stitch-chart/ , because the chart below it seems only vaguely related. (This was the topic of a question on Ravelry: https://www.ravelry.com/discuss/techniques/3904245/ )

Shown with a cast-on count of 29 stitches.   Getting chart...

  • Rows 1 and 11 (RS): P1, *k4, k2tog, yo, k1, yo, ssk, k4, p1, repeat from *.
  • Rows 2, 4, 6, 8, and 16: K1, *p13, k1, repeat from *.
  • Row 3: P1, *k3, k2tog, yo, k3, yo, ssk, k3, p1, repeat from *.
  • Rows 5 and 13: P1, *k2, k2tog, yo, k5, yo, ssk, k2, p1, repeat from *.
  • Row 7: P1, *k1, k2tog, yo, k7, yo, ssk, k1, p1, repeat from *.
  • Rows 9 and 15: P1, *k2tog, yo, k9, yo, ssk, p1, repeat from *.
  • Row 10: Knit.
  • Row 12: K1, *p3, ssp, yo, p3, yo, p2tog, p3, k1, repeat from *.
  • Row 14: K1, *p1, ssp, yo, p7, yo, p2tog, p1, k1, repeat from *.