I experimented with a couple of things making this block.
I read an article this week about the fact that starching actually shrinks fabric. I think especially if you don't pre-wash. Guilty!
It's probably common knowledge to most of you but somehow I never thought about this. I now realize that starching while making my blocks may be a leading reason I've been having trouble with my blocks sometimes being too small. There is also sometimes puckering when I starch. Maybe because different fabrics shrink at different rates.
Anyhow, this time I decided to starch the fabric before cutting. It really made a difference!
I think this may be the straightest, flattest block I've ever made, even though it doesn't look like it in the photo.
Because I figured I had now "pre-shrunk" the fabric, I also felt comfortable spraying some more starch and pressing the seams open, which also helped it lay flat.