i think it's fair to say that the former pros have tried everything. how can they not? it's in their blood. it's fair to say that the older, retired players (borg, connors, mcenroe) are not taking huge cuts at the ball like the current pros because they're physically more fragile or softer than their playing days, so using the poly can be more of a detriment to their game. poly is really hard on the arm and i have tried it once (strung at 60 lbs
) and the feel was totally different. my strokes are very long and generate a great deal of pace, but i could not move the ball with the poly. the string bed felt dead. stringing at lower tensions would help, but again, in my mind, when you've played gut and multifilaments, the poly response is just too harsh.