Halland mittens

Hi Everyone!
I have been learning so much from reading all the posts and watching the videos. I am currently knitting the Halland mittens from the Folk Mittens book. I finished the first (left) mitten and am working on the 2nd (right) one. If anyone has this book, the chart is on page 41. For the life of my, I cannot figure out why I am supposed to begin the pattern for the right mitten in the middle, rather than the right edge of the chart. It seems to me that it doesn’t change the pattern or placement of the thumb in anyway…it just confuses me. Am I missing something??

On a side note, I’m using these mittens to practice 2 color knitting - holding one color in each hand, per the video on this site. It’s not quite as even as if I was doing it all with my right hand, but it is soooo much faster.

Thanks for the help!