The couple of posts about the breaking point of Dynaglide seems to be inline with the find print on NERs data sheet.
Tensile strengths reported are approximate averages for new, unused ropes. To estimate the minimum tensile strength of a new rope, reduce the approximate average by 10%. (The Cordage Institute defines minimum tensile strength as two standard deviations below the average tensile strength of the rope.) Stretch data tested to CI 1500-02.
If one wanted to get technical with the weight issue they look up the specifications mentioned in this portion of the fine print.
Compliance to the above specifications is based upon testing according to the Cordage Institute Standard Testing Methods for Fiber Rope and/or ASTM D-4268 Standard Methods of Testing Fiber Ropes. Weights are approximate and may vary +/- 5%.
The data sheet can be found here