I don't have any bows under 55 pounds at my draw length. My arrows most often fall into the 650-680 grain weight area.
Samantha on the other hand, who shoots 42-44 pounds out of her longbow shoots 500 to 525 grain weight arrows.
I like the 10-12grains of weight per pound rule, and I have recently gone to the Extreme F.O.C., with it proving itself this past weekend.
I had a doe come in at about 23yards(walked distance off after the shot)that was getting ready to leave. In this part of Texas(Leon Co.), we have to try to take our does(we are allowed two) during bow season, because during the regular season it is bucks only, we focus on them during the regular season with out bows.
I had been seeing a lot of hogs, and not as many deer so I decided to take the shot. She was broadside when I begain my draw, then without warning turned to the left giving me a hard quatering to the left shot. It was about as close to straight away, without it being a "Texas Heart Shot". I picked my spot on her right ham, and the arrow was away.
I watched as she dropped her head, let out a bleat,and ran like her tail was on fire. I thought I watched her drop, but was not sure.
I waited two more hours, thinking that maybe a hog, or the buck I was hunting might show up. The shot was taken at 0801hrs, and I took up the trail at 1000hrs.
I walked to where she was standing when she was hit, no blood, followed her path, as seen from my blind to the logging road, there was blood everywhere at that point. I looked up and found her laying on the edge of the road. She covered thirty yards and piled up with her nose in the dirt.
The heavy 2018, Wensel Woodsman, 75grain steel broadhead adaptor, from a PLX Black Widow long bow 55 pounds at my draw, traveled the length of the doe, from righ ham. The arrow was protruding from her left front chest, withe 16 inches of arrow sticking out!
Postmortum showed the heavy arrow destroyed one lung, and nearly cut the heart in half. I had never had this type of penetration with my lighter weight arrows in my life, and I have shot a lot of game.
My bow shot silent, the arrows fly true, and when they hit what I shoot at they do the job. Is it a requirement for everyone to shoot heavy arrows, no but the advantages far out weigh the disadvantages.