it doesn't. you could probably spend a half hour and look at a hundred games and know for sure what the answer was (only 3pta, only 3pt%, or a mix - i suspect its a mix). what that mix is, of course, could take further refinement.
the real problem here is, if CS told you the answer, would you believe it? i guess i am much more of a skeptic than most of the coaches around here, but i sure as heck would not take it on faith. id still have to go out and do the study to know, to me CS can never be more than a verification. but then again, neither can the belief of a veteran coach, even if its OR or lostmyth or any other of the coaching elite. even when CS and the vets agree, its happened a number of times on major issues, they can still ALL be wrong, and someone who everyone writes off like colonels, furry, and tmac (all BEFORE they turned things around - which they all did - no disrespect guys in the slightest) could be right. that exact scenario happened with pulldowns... it was tmacfan and furry_nips vs all the games greats AND cs. and guess who was right? yup. tmac and furry.
so, i guess all im saying is, no it doesn't have to be a mystery. but someone telling you the answer doesn't make it any less of a mystery. got to go check it yourself.