What Prism said, especially this:
Originally Posted by
Prism99
I also think you would find it tiring manipulating all that fabric underneath the arm of your machine as you sew around each plate, even if you can stabilize the background sufficiently. So much excess fabric will also make it more difficult to applique accurately.
There is definitely a reason why appliqueing the plates onto blocks, then assembling the blocks together is the standard design - it's MUCH easier to simply sew straight rows of blocks than to wrestle with all that fabric.