Split Single Crochet Stitch

My Honeycomb Socks in the Fall 2010 issue of Interweave Crochet use a split single crochet stitch for the foot. It is an interesting stitch and not one that I've seen used widely.  The definition is: insert hook between the 2 vertical legs of the next stitch, yarn over, pull up a loop, yarn over and pull through 2 loops on hook.

The part about the "2 vertical legs of the next stitch" is the part that is out-of-the-ordinary.  I've created a photo that I hope will help!