Spinning from Variegated Roving

I came across this interesting video about spinning from variegated roving, and the different effects you can get depending on how you handle it. I really enjoyed the comparison of the spun yarns and knitted swatches.  I could see how something like this would be very useful in a yarn shop, where it's not always easy to extrapolate from loose fiber or roving to spun yarn, or from skeins of yarn to knitted or crocheted cloth.  I love many different types of variegated fabric, so it's fun to examine the color dynamics and geometry of how that works.