I personally haven't noticed any difference in my poi but I see where it might happen if a backpack is spongy. Some backpacks offer an optional bag rest that mollie attaches to the pack. Personally I like options simply because every hunting situation is going to be somewhat different. If you don't mind a little extra weight you can have a bipod on the rifle, a bag rest on your pack, and a tripod in your pack if you have to make a standing shot. Just keep in mind, " a man has to know his limitations " practice will reveal the answer.