Originally Posted by
FBinNY
IMO, this has reached, and seems to have passed it's service life. When I see this kind of stretch, I suspect overuse of dressings such as Proofhide. These are fine if used sparingly, but if the leather is drowning in it, it gets too supple and stretches like taffy leading to this.
Yes, although Proofhide doesn't lead to this if applied as recommended. However, leather softeners like neatsfoot oil can cause this sort of excessive stretching