Also, it's always seemed to me that havok items bounce around way too much in the first place.
The fix is to go into the [HAVOK] section of the ini and change iSimType=1 to iSimType=2. This dampens the "liveliness" of all havok items, similar to the way "Realistic Physics and Force" does with NPC skeletons. Everything still falls realistically, but they don't bounce around as much.
It also lets you enable bAddBipedWhenKeyframed without any of the previous drawbacks.
Interesting Note 1: Oblivion overrides the ini setting and enables bAddBipedWhenKeyframed when you start a new game. It stays enabled until you exit the game and reload. You can check it by starting a new game and then walking on top of dead Renote and assassins and rats and watching them move around.
Interesting Note 2: In their default ini settings, Oblivion disables bAddBipedWhenKeyframed, Fallout 3 and FNV both enable it, but then Skyrim reverts to disabling it. I assume iSimType=2 would work for all of them but I haven't tested it.