Way in the past, when I saw the Japanese Darning Stitch in books, I thought it must be an easy stitch. After giving it a half hearted try once, it turned out all wrong and I abandoned my attempt. That is why I choose this stitch for Sunday Stitch School's tenth lesson. I HAD to master it.
Once I got the hang of the spacing, it was easy-peasy and most enjoyable. I think it would indeed be a decorative darning stitch and fun to add to a Crazy Quilt seam, maybe with other stitches added.
I wanted to explore more, but did not find the time, so here is the set homework :
Chitra of Jizee6687's weblog has some stunning ways of working the Japanese Darning Stitch. Check them out here.