> Exten-sive structural modeling of the Arecibo Telescope, independently confirmed by laser cable sag surveys, validated that under all static and cyclic loading conditions, the cable loads barely exceed half the nominal cable strength.

I have a feeling such measurement and modelling might have been wrong.

It's easy to miss some oscillation mode, particularly high frequency longitudinal wave's in the cables, which couldn't be picked up by a laser survey due to the kilometers per second these waves travel.