Assuming the recruit has numerous high potentials, my rule of thumb on redshirts is to expect the total improvement to be somewhere near the overall WE of the player.
here's a list of the guys I've redshirted the past 6-7 seasons at my two D2 teams. (players WE, total points of improvement season + offseason)
WE12 +29, WE32 +38, WE34 +40, WE35 +40, WE39 +52, WE43 +43, WE46 +50, WE47 +50, WE55 +63, WE57 +62, WE59 +52, WE70 +81, WE79 +94
2/19/2011 2:05 PM (edited)