Hi all, May I be enlightened on the number of times can an original high-end racquet (e.g. YY VTZF) be restrung? For example, if a racquet does not have any collisions with other racquets, does this mean, the racquet is safe to be restrung for the rest of its design life? And if a racquet is always strung at about 30lbs, does it reduce the racquet's life span? I hope this questions can be answered. Thank you so much.