Originally Posted by Mouseskowitz
This is talking about kernmantel rather than amsteel so it may or may not apply. This an except from Life on a Line by Dr. Merchant which is a cave rescue book.
So, my thought is, if a portion of rope has been flattened it may cause a permanent weakening of that section at the microscopic level. Will this cause failure with our application? I'm speculating probably not. If you take degrade 1600lb by 60% you still have 640lb which should still hold us in most hammocking applications.
Internal abrasion damage of fiber on fiber was a serious problem of early Kevlar cordage. it was particularly dangerous because disintegration was taking place within an outer protective cladding or outer braid.
Dyneema / Spectra (and probably current versions of other hi-tech synthetic fibers) don't have this characteristic. Testing of bending fatique resistance is done to thousands and tens of thousands of cycles.