An improved load leveling yarn has a force-displacement profile that maintains desirable properties of previously known yarns (as exemplified in U.S. Pat. No. 5,830,811), but exhibits a lower elongation at a stress that is greater than the IBS but less than or equal to 1.8 grams/denier. Especially preferred yarns are produced from PET with an IV of greater than 0.9 and epsilon caprolactone (at a ratio of about 90:10) under copolymerization conditions that allow reaction of at least 95% of the added epsilon caprolactone. Such yarns can then be formed into a web to form specific products, and especially seat belts.