I was with some beginners about a month ago, and a fellow was carrying about 25 pounds - not bad, all things considered. However, when I was behind him, I noticed that he had two one-liter water bottles in the shove-it pocket on the front of the pack (the side farthest from him.) His water bottle pockets were empty.

I asked if he minded if I moved his bottles to try something; he said OK. I put them into the water bottle pockets, which moved four pounds (16% of his load) toward his natural center of gravity. His reaction was "Wow - that really makes a difference! The pack isn't pulling away from me any more!"