I re-did this block three times. Death-defyingly wonky in the first attempts. Scant seam allowances way too close to the edges and so on. But I had one that I put into the envelope and taped shut. A day later, I ripped the envelope open and spent a good bit of time with the seam ripper on the front porch.
Ahhh, that's better. Hopefully there are no swear-word-inducing angles to this one. :-)