demo,,,If I only had a nickle for every miss due to yardage mis-judgement.......speed does away with some of those misses within10 to 40 yards and remember the formula, speed squared times mass divided by 450240 gives ke,,,,(speed squared not mass squared) all things being equal 30ftlbs will put an arrow thru a deer, but 65 to 100 ftlbs will smash bones and all with the right broadhead.....