The double strands allowed the weft to be seen just a little. Because they were in different sheds on this band the result was a bit of a zig-zag. I thought this ended up pretty neat and wanted to try it some more on other projects.
On the next band I used a variegate wool that was a thinner weight yarn than the warp. I think it was sold to be used for knitting socks.
The result was a look that to me seems similar to using yarn that has flecks of color. But instead of all the yarn having the flecks, you can control where the color variation is and where it isn't. It ended up a very subtle effect on this band. Perhaps with yarns that contrast more the effect would be greater.