Yep. I have to admit I long held onto that point of view myself. But according to the arrow lethality studies on live game and dead animals that Dr. Ashby has done, smaller diameter arrows really do penetrate better, all else being equal. Heavy arrows penetrate better than light ones. High FOC arrows penetrate better than low FOC arrows. I have to go with the data over gut feeling. So, it looks like if you want maximum penetration you want a heavy, small diameter arrow with a very high FOC.