I'm going to have to try tying some grosgrain to the corners of my burrow and give this a test go.

I was thinking instead of GG, you could ask Adam to sew eyelets in the drawstring channels near the corners. When in UQ mode, fish out the drawstring and attach your shockcord it. Might help the ends cinch up a little tighter that way. Then again, it's not a differential cut quilt, so maybe tighter isn't necessarily better.