These ratings may have made sense when rackets were all straight beam and had the same kinds of standard string holes and grommets. With racquets now often having several variations in the beam from end to end as well as having other forms of "give" or flex engineered into the head (woofer, speedports, teflon....), the technique of measuring flex only at the throat seems woefully inadequate. The number of posts on this board questionning the accuracy, or meaningfulness, of a particular racquet's RDC number points up the lack of satisfaction. A more meaningful spec might be to measure flex at a few locations on the racquet, or even to measure "dwell time" for a ball shot at a racquet under some sort of standardized conditions. I find I pay less and less attention to the RDC number.