Pantyhose are truly a multi-function item! Dryer filters, hair nets, and hop bags can all be made from leftover pantyhose. Since you have this endless supply of recycled pantyhose, maybe you should consider a marketable item made from them! In any case, boiling hops in a hop bag probably will result in a decrease in hop utilization. The magnitude of the decrease will vary depending on how much hops you try to cram into the hose and will be minimized by using enough hose not to overly restrict the movement of hops during the boil. Hop utilization requires constant tweaking, and you will need to tweak your hopping rate for your pantyhose bag just like anything else. The best way is to simply use your palate and use more or less hops based upon your results. I honestly don’t know of a single fancy calculation that you can use to compensate for decreased utilization due to the weight of hops per length of pantyhose. As you suggest, pantyhose are not just for hops. You can use them for spice bags, dry hopping, brewing your morning tea, or whatever floats your boat.