what?? you need to go back to basic physics.. Just for the record take any bow any draw length. shoot a 300 grain arrow you will get such and such a speed and so many ftlbs of KE. now take same bow, same draw length, just change arrow weight and shoot, you will get slower speed but KE will always,I repeat always, be more. and the heavier the arrow gets the more KE you will get, even though it is going slower. You will need a Chronographs to measure the speed at the bow and and grain Scales to measure the weight of the arrow.

At least it's always been that way and I don't see why physics would change just because you bought a bow and arrow.