I just watched this Youtube video by Leah Day:
http://www.youtube.com/watch?v=Bv6TqdwjiXo
and she mentions that this is for wall quilts. I imagine this is because Leah Day is working on a very small scale and so much thread will stiffen the quilt. I have Karen McTavish's book and DVD and am looking forward to experimenting with the technique. However, I'm into making bed quilts and child quilts, not wallhangings.
Has anyone done McTavishing on a bed quilt? How did it turn out?