I have met up with TypeRx in my travels and hit against him. His hitting style is very Nadal-like - he hits with more average topspin rpm on his shots than anyone I’ve hit with. He uses massive heavy spin as his primary weapon to make it difficult for his opponent to control the launch angle. Given his preferred playing style coupled with his need for comfort and durability, it’s not surprising what his current string choice is. I think a full bed of gut or soft multi would be counter to his spin-based game, and he’d break those in less than an hour anyway.Anyone thinking they are healing their arm by playing with Kevlar is confused. The high differential with a soft cross string may make it tolerable but using Kevlar to heal is bad thinking. Using the stiffest string on the planet is not arm curing. Low tension gut combinations, multi or synthetic gut are more in the realm of playing with set ups that could assist in arm pain provided the frame is fairly flexible.