LOL! You and rulers!
I haven't seen this one, but it looks like it's part of her "Setting Solutions" techniques (for lack of a better word).
FWIW, I thought SS was one of BEST quilting books I ever read - yeah, actually read it.
Again, I don't mind doing the math or chopping off the extra fabric if I used over-sized triangles or squares to make snowballs, so I don't know that I'd buy it
(btw, I thought of your earlier post from a few weeks ago on that ruler you bought to make HST/QST with the fudge factor already built in.
fyi, the new next-best-thing being demoed (in the pursuit of perfect HST's) at Houston was the Bloc-Loc
http://www.blocloc.com/ , and they were flying off out of the booth.
NAYY, and I didn't buy it either.)
I like the idea of doing that as a guild activity.