I just let go of my paddle and hold everything down with my hands in rapids
. Seriously, I'm a strap in kind of guy. Bill Mason advocated tethers and later changed his mind about them preferring to tie or strap everything in. More buoyant gear that is in the boat, means there is less nice heavy water in it. The main thing, is that if you are going to tie or strap in your gear, it is less effective, and arguably more dangerous if you strap or tie across the gunnels or thwarts, as stuff will want to float up when the boat is upright and full of water. Letting stuff float completely free, assumes that it is just a short rapid with a big slow pool at the bottom for recovery. But three or four packs, a couple of swimmers and a boat, is a lot to keep track of for your rescue boats.