Afghan sizes are provided for after blocking.

UPDATE 12/29/2013: LPC instructions have been updated to show "slip 3 to cable needle and hold in front, p1, k3 from cable needle". PDF has been updated.

ERRATA:
Abbreviations indicate

LPC: slip 2 stitches to cable needle and hold in front, p1, then k3 from cable needle

It should say slip 3 stitches to cable needle…
PDF has not been updated.