I have read that some pros such as James Blake use Luxilon ALU Power for their entire stringbed strung at a fairly high tension (60 or over I think). I have also met club players who use Lux ALU Power for the entire racquet strung anywhere between 58 to over 60 pounds. And these club players don't really have great technique or well-developed strokes and are not necessarily always young people in the greatest shape. Yet, all these people do not seem to have or develop any elbow, wrist, or shoulder problems from using such a stiff string at a high tension. They don't seem to follow the Luxilon advice of reducing tension by 10% or use hybrids. I have used Lux ALU Power Rough (which is basically the same string except for texture) in a hybrid with natural gut in the crosses and the Lux in the mains strung at 58, with the gut at 60. Even with that set up (which is supposed to be softer), I still felt elbow and wrist discomfort from the Lux. Granted, I already have a little bit of an existing shoulder issue (bursitis), but generally never have elbow or wrist discomfort from tennis. Why is it that some people can use Lux ALU Power or Lux ALU Power Rough for the entire string bed and not have any arm problems? Are they just in better shape or is it something that will simply vary from person to person?