What you're not seeing is the ends, carefully tucked under the knitting! I like to weave them in after every few inches of knitting.
I prepared for the new row of blocks last Saturday and I'm working on it now.
As intarsia projects go, this one is quite easy. With predictable color changes, it's not hard to memorize the pattern and just concentrate on the knitting.
One row of blocks finished, 15 more to go, counting all the rows, front and back of the cushion.