i have that book ..isn't it
wonderful!? 
..but ..i bought it for the history, primarily, i may or may not do one of the quilt patterns in it. as for the knife edge finishing technique you mentioned ..it is something i have used on many projects over the years ..all quilty projects. it's nice for anything from placemats to quilts, especially quilts i make using minky type fleece or faux fur quilts for my grand treasures. if you use it you can also do a straight line of stitching 1/2" or so in from edge after finishing the hand stitch of two folded-in edges. this aditional line of stitching looks nice, the bulk of four fabric layers plus the batt gives a bit of diminsion.
...note:
when using this technique i fold either the top or backing over edge of batt when folding in to stitch. i like the fullness of batt to extend to the very edge of finished quilt regardless of type of edge finish i do --folded in, brought around fr back or binding.