I tried an experiment with this project. As I mentioned, the yarn is a gradiance set and it is recommended that you do a series of transition rows between the skeins, and I have done that on the other three shawls that I have knit using gradiance sets. But this lace pattern is taking up most of my brain power and I just didn't want to deal with the transition rows, so I decided to see if the yarn would do all the work for me. I knit until I was almost at the end of the first skein and then I grabbed the second skein and started with a length that matched the color of the first skein and started knitting. And I am happy to say that the colors are transitioning beautifully.
Postscript: Well, I just finished going back over that last row in Chart C and I definitely made a mistake, but I believe it is because there is a mistake in the chart. After the two sets of stitches that are gray, there is a motif that the chart indicates should be knitted twice, but when I did that I actually ran out of stitches, and if I leave out that second repeat, everything works out. It only affect the second half of the row and the mistakes were easily fixed. At first I was just marking where the mistakes were with slip on markers, but it wasn't just a matter of picking up a missed stitch, so I decided I needed to just fix them as I went along by slipping the stitches from one needle to the next until I got to a spot where there was a mistake, fixing it, and moving on. We'll see how good I am when I start the next chart.