I have made a couple of pair of nalbinded (nalbound?) socks. I think much
of today's nalbinding uses fairly thick wool compared to what they were
probably using then. If the nalbinding uppers were felted it would help to
strengthen them. Maybe these are some sort of indoor slippers. One can
grease leather to help make it waterproof, but wool absorbs water like
crazy- - never bump into a sheep that has been out in the rain!

Generally the thickest part of a hide would be the shoulders, then the back
and the sides. One would assume the shoulder would be used for the sole and
the flared part of the upper leg above the hock would be a natural for the
leg part of a boot. I don't think there is anything implied about using
scrap leather.
Grace
Fred and Grace Hatton
Hawley Pa