Popcorn stitch pattern interpretation

Popcorn Stitch (multiple of 4 + 2 sts)
Row 1 (WS): k1, *(k1, p1, k1) all in next stitch, p3tog, repeat from * to last st, end k1.
Row 2: P
Row 3: k1, *p3tog, (k1, p1, k1) all in next stitch, repeat from * to last st, end k1
Row 4: P

QUESTION_ what does “all in next stitch” imply? Does it mean to complete the entire row in k1 p1 k1 p3tog, k1 p1 k1 p3tog repeats and end in k1? And does anyone know if this stitch pattern is reversible?

Thanks in advance.

The pattern is over 4 stitches. In the first stitch, you knit 1, purl 1, knit 1, all in the same stitch. The remaining 3 of the 4 stitches are purled together. Next set of 4, k1, p1, k1 all in the first stitch; purl the remaining 3 together. Etc., across the row. That’s my best shot, though it may not be any clearer to you than the original.

I get it- just may be more complicated than I expected as a newbie! Do I leave the stitch on the left needle until I have completed all three stitches k1p1k1 and transfer to the right after the last k1? Will it look good on the reverse side?

Yes, you’d knit 1, bring yarn forward and purl that same stitch, take yarn back to the back and knit that same stitch, then slip all of this off your left needle.