I've done some of these things - sewing without bobbin thread - and of course I was chain-piecing. Quilting folds of the backing fabric into the quilt - yep, that too.
No quilting in the nude though - I don't need any of my junk to fall onto my sewing area! :shock: :mrgreen:
The worst things I've done both resulted from forgetting to check the back of the quilt - both times, I had briefly worked on another project and changed the bobbin tension and it was way too tight when I put the bobbin back in for my quilts. Both times, I ended up with horrible quilting on the back.
It felt like I spent a week with the darn seam ripper on one of those. The last time I did it, it wasn't so bad, but unsewing is never a feel-good activity. There's just no satisfaction in it at all.