Tokyo Subway - Block B1 done

Now there are two blocks done. I laid out the whole top row, in order to see how well my scraps came out color-wise. So far, I'm quite happy with the purple, but not so much with the orange. Working on this quilt has shown me some places in which my stash is weak, namely in the orange.
But when I put both of these blocks side by side, it looks nice - I am very satisfied with Oh Franssons! design. And it's easy to put together. The technique I'm using to align the small squares is a non-locking technique, in which the seams are pressed open. Before sewing strips together, I only finger-press, and don't use an iron until a block is done.
I've had lots of success in the past using the locking technique, but I decided to try opening the seams instead and pinning the seams exactly together.
When I do the pinned open seams technique, it shows me immediately where one seam is slightly too wide or too narrow. When I trusted the locking technique I found it easier to ignore slight misadjustments. In engineering, we have a technique of manufacturing called Poke-a-Yoke, in which the assembly method prevents errors. The open pinned seams technique is my quilting Poke-a-Yoke, since it makes it harder for me to make an error.
What's that I heard you say? That the problem is not in the locking or open-seam technique? That the real problem is that I used to ignore little mislignments rather than fix them immediately? Sorry, I choose to be in denial about that (puts hands over ears and sings LALALALALA in a loud voice.)