i saw some strings on a web site and the power ratings did not make sense to me. the strings that got a higher stiffness rating by the racquet sports industry are supposedly less powerful than the some of the softer polys. i thought the stiffness of the string determines the power level too. i guess the power ratings were the manufacturers ratings. im trying to find the most powerful polys out there and i have been searching by the stiffness rating. is that wrong? can some softer polys be soft and responsive and low powered at the same time?