It gives the feed dog something to grip, other that the fabric. I also use it when sewing appliques.

Love the minky back.

How do you do the corners to keep from having so much bulk. Planning on trying one very soon. Thanks

same as other quilts-i made a tutorial for the way I bind quilts https://www.quiltingboard.com/tutori...s-t310370.html
(it has pictures)