What these two women are doing may or may not be a specific technique unique to them, I can't really tell. You do find similar things on the extreme edges of quilting, where people are exploring it as an art form to be hung on the wall, rather than as working bedcovers.
What people are doing with quilts has become really spectacular over he past 30 years or so, and there is a very strong "quilts as art" movement that has produced some stuff I find mind-bogglingly elaborate and super-rich for being quilts.
Embroidery entered quilting in the 1880's, I believe, with the sudden popularity of the Crazy Quilt, whose irregular shaped patches are always bordered with elaborate embroidery stitches. Alot of quilt artists take the use of embroidery thread from that tradition, and go wild with it.
Beautiful works here...I am an avid quilter myself, and it is a very "mathematical" art because of the symmetry of the pieces. But this takes art would see so abstract yet exact to have to create these.