I'm just in the process of quilting this pattern.
I too saw it on the board a couple of weeks ago.
It was made with a Creative grids curves for squares 6" x 24" ruler. Squares can range from 5" to 10".
Whichever size square you decide to cut, when sewn together the square works out 1" smaller.
I found it fairly easy as the curves are very gentle. It's abit like piecing a Drunkards Path block.
If you plug into creative grids video demonstrations they show the various arrangements that can be made using the ruler.
Will post a pic of my WIP so you can see what it's like.
Northern lass