kodiak and arthur are right on. bend at the waist and youll have no problems putting the arrow where you want it
alot of our local 3d shoots have platforms and stands built to shoot from. funny to watch everyone in my group NOT bend at the waist and send them high. even the guy with the kisser button AND peep site
not me...thats where i add onto my score. bend at the waist and keep your anchor points the same and youll be fine....make sure you practice it though!! takes a little getting used to