i dont know about 20->70 but there is a REALLY good study on this somewhere that makes it clear how often different categories go into different ranges. i generally consider +40 outside lp/per a 'realistic best case' so i think that is a reasonable way to look at it, but i do think there are differences, like def and passing have more odds of getting up near 50 while ath/spd that is pretty darn unlikely, or something along those lines. the study captures all that fairly well though. i have no idea where it is but i'm guessing someone who regularly reads these forums has it bookmarked or whatever.