I'm just the opposite--my shoulders are so pressure sensitive that I have to make sure all the weight transfers to the hip belt!

That being said, your hubby should keep his pack very light (most men can carry 20-25 lbs. in a beltless pack). In other words, he's going to have to work towards the "ultralight" category (base weight of 10 lbs or less). I agree with Rick about a sternum strap or perhaps a non-weight bearing hip belt (fastened loosely) to reduce bouncing.

You are probably going to have to look at the lighter end frameless packs from such "cottage" firms as Gossamer Gear and Mountain Laurel Designs to find packs designed with no hipbelt or with a removable hipbelt. I did a little looking and found that there seem to be fewer packs with an optional hip belt than there used to be, but there are still some around.

EDIT, LATER: Check out the ZPacks Zero, too. Another pack where you don't have to pay for a hip belt you can't use!

My first backpack trip was back in 1941 and back then, most backpacks didn't have hip belts. I carried 5 lbs (I was 6). My mother carried about 60 and my father about 75. I don't know how they did it!