CI Fairfield and I have been trying to figure this out...the "sinew" she is referring to is wrapped around my doll's waist like a belt. That's how she came to me, used, so we're not sure if it's really a belt or something meant to wrap the blanket around her. I like the looks of her dress without it, the way CI Fairfield's doll is shown.
Jeanie, I also used your method to wiggle my doll back into the cradleboard without undoing the laces. I did loosen them just a bit, and re-tightened them once she was back in.