I put the pockets on the wrong piece.
wrong side. Now it makes sense that when I sewed the front and back pieces together with my welt flap in place, the hole and pocket didn't really flow.
Well, that's okay. It had to come sometime. So, I spent the next evening carefully ripping out my perfect stitches. Since I had already cut into my fabric to make my pocket opening on the wrong side, I needed to improvise in order to fix it. Luckily this turned out easier and lovelier than I could have hoped. Maybe even better than the original instructions!