Originally Posted by Murray Mound
1- you can use any string you want on a vortex.
2- mark woodforde used thick 15 guage
3- there is a debate on thick vs thin. Thin supposedly gives more bite but another school of thought says thick gives more spin becaise there is more material touching the ball thus creating more spin.....and then there are others that say it's all racquet head speed and string doesn't matter . Bottom line: no one really knows.
The original Hi Ten series were based on the idea of an extremely open pattern. However at that time, no-one played with polys. Because of the open pattern, the recommendation was the string very very tightly - (not sure if I'm remembering correctly, but I thought somewhere over 80lbs??). The higher tensions were the only way you were going to get any control out of a string pattern that open - and I guess the thickest strings weren't going to break as easily.
Wasn't sure if you knew this - thought I'd add. Would have been interesting to see those old frames with poly set ups.