I've come to the conclusion that the most challenging part of this mystery for me was the tri rec squares. I measured accurately, at least I thought I did, but my tips are off on nearly all of them. I'm putting my rows together now and have decided to focus on matching up the neutral pieces rather than the seams since my blues are so bright that it really stands out if the neutral points don't match. However, that means that my seams are off on nearly every intersection, not by a lot, but enough to annoy me. Luckily it seems to actually be working out so far, but it will be interesting to see how close to 75x75 my wonky quilt top actually is when it's finished.
Does anyone know why my tri rec squares are off? I will say this mystery has humbled me and made me realize I'm not as skilled as I thought I was, but goodness, I can't wait to work on a few plain old square pieced quilts just to restore my confidence! I think the next time I see a class offered that uses the tri rec tool, I might try to sign up for it.
I guess Bonnie really knows how to stretch a quilter's skills anyway!