Making Something Good Even Better: a Tutorial on I-Cord Edges in Stocking Stitch

Ever since Purl Soho brought out its Top-Down Turtleneck Cardigan, I've been obsessed with it. It's not just the streamlined shape in a fine yarn; it's those beautifully clean front edges.

So, I tried out the method on a swatch -- and I wasn't happy. Call me fussy, and over-obsessed with details, but the two front edges did not match in appearance, and the left front edge looked sloppier than the right, especially on the wrong side. Why would this matter to me? Because when you wear a cardigan open, those little I-cord facings show.
Last year when I played with this, I made notes about the experiment in my Notebook #11 (I'm currently on #13) and, being caught up in other things, didn't get back to thinking about it again until this week. I'm working on a little, light-as-air mohair cardigan. I don't intend to add buttons to it, or seams either (not that I do that ordinarily anyway) because I don't want anything to weigh down the floaty fabric. It's something to wear in the spring/early summer when you just want a whisper of something to cover up your bare arms. (We're aiming for a high of 9C today, so I have a little time before I need this.) What I really want on this piece is lovely, clean, self-bound edges just like the ones above--except better.
When I looked closely at my earlier experimental swatch, I noticed that along the tidy edge, the three I-cord stitches were in fact twisted; they looked as though they had been knitted through the back loop. This was due to the fact that the instructions from Purl Soho were to slip those three stitches KNITWISE. Of course, every experienced knitter knows that the easiest way to tighten things up is to twist the stitches in question. The problem for me was to figure out a way to replicate this on the other edge. The solution? To knit those stitches at the end of the right side rows THROUGH THE BACK LOOPS before turning the work and slipping them PURLWISE at the start of the wrong side row.
Let me summarize:

Try a swatch with 16 stitches. Cast on by the longtail method and for the nicest top edges, make sure you cast on with a knot-less method.
Row 1 (WS): (Sl 1 purlwise) 3 times, purl to end.
Row 2: (Sl 1 knitwise) 3 times, knit to last 3 sts, (k1tbl) 3 times.
Rep Rows 1 and 2 to desired length.

This is what you'll end up with.

Right side.

Wrong side.

Remember, this is unblocked mohair, so things look a little loose and wonky, but the important bit is that both edges now have twisted stitches and mirror each other. After blocking, these edges are going to be perfect. I guess I'm a knitting nerd.