One more question, a quick Google search seems to suggest that some find this way of finishing to be LESS durable. One blog I found (
https://www.thespruce.com/sew-knife-...inding-2821319) specifically said to only use this kind of finishing for wallhangings or small quilts. Have you really found this way of finishing to be as durable as traditional binding?[/QUOTE]
In about 1995 I bought an antique, 2-color pieced quilt appraised as from 1860's, the quilt has the knife edge for binding and it is all intact. Actually bought it for $1 at an estate sale but the quilt was in the horse barn. I washed it as any other quilt and it held up great with no issues.
Nice to know a bit of history on the method. It does make sense if the maker did not have extra fabric for binding.
Thank you for bringing up the topic.