The shawl is wide and in order to half the stitching time the material is folded in half and stitched through two layers. This technique is often used in Rajastani tie dye pieces. I've seen only a few pieces like this done in Japan traditionally. The Japanese would go through the extra stitching to get a specific pattern. I like the mirror image actually.
Here are a few pictures of Kawamotos san's shawl from a few months back.