This afternoon I'm sewing together the rest of the floral and white Disappearing Four Patch blocks, and I noticed one detail that should be mentioned. When cutting the two part block into 6 pieces, be SURE to ALWAYS position it the same way on the cutting board. For instance, if the darker fabric is on the left, ALWAYS position it on the left.
Likewise, when laying out all 12 pieces for the complete block, ALWAYS lay them out with the lights and darks in the same positions. Failure to do this will lead to seams that don't nest properly. And nicely nesting seams are really the whole point of making the block with this method.
It's amazing how a simple mistake in arrangement can result in "orphan" blocks! Good luck with your sewing!