Not to mention if the back end of the arrow is equal or heavier than the front end of the arrow it takes more fletch, "drag" to stabilize the arrow resulting in tailing etc...think of it this way, if the back end was heavier and there wasn't adequate stabilization, the back end would want to become the front end. It never happens but out of a poorly tuned bow, it could. A low FOC only compounds tuning issues.