I realized I had cut up the two focus fabric FQ for my second Optimism, twin. I laid the cut up bits together and took a pic. The other pic is my 8 point stars. Focus fabric (none in this block) is left & my first Optimism is on the right.
If you looked at her original grid, you see she makes (prob 6") smaller blocks, then frames them up to 7-1/2, and puts 4 together for the 15" block. I enjoy math and making it work. 15 divided by 2 is 7-1/2, divided by 4 is 1-7/8". Plus SA 1/2 is cut 2-3/8."
Not typical quilt numbers, but eminently doable. Happy to provide complete write up if anyone would like to follow suit.