Re: It's (not?) all in the hips
Well, there's moving the hips and then there's moving from the hips. The torque you mention sounds like twisting at the waist. I've been specifically corrected to never twist. There are definately techniques I practice that could give the appearance of twisting. However, the shoulders always remain aligned with the hips (well, that's the plan, anyway). All of the right side moves together and all of the left side moves together. Legs may turn to move the hips, but the upper body stays stable on top.
You know, after reading Mike's post ... if I'm reading it correctly, sounds pretty close to how we practice at our dojo. Except that I wouldn't say that we throw down so much as up (then, down becomes easy). Uke's momentum or attempt at gaining back their balance is what can cause them to be "projected" away.