That is benefit #1 of separation in any plane, imho: range of motion for dynamic balance!
Razie, given this statement above (which aligns with my experience), I don't quite understand what's written in your next post. Which seems to imply there's little ability to control lateral balance.
As discussed: when bending forward at the waist, to stay in balance, the hips naturally move back. So when you turn, the hips simply move in too.
Remember, angulation does not move the average COM to the outside of the turn, it merely allows more inclination at the legs, i.e. more angles.
Seems to me there's a few factors in play.
Firstly there's the amount of mass above and below the 'original' BoS/CoM lateral balance line. Mass below the line will tend to bias lateral balance in favor of gravity (so inside of turn) and mass above that line will tend to bias balance in favor of 'centifugal' forces (to the outside of turn).
Secondly, the distance between the lateral pivot point (typically inside edge of outside ski) and the mass affects the moment of the forces that must be summed to determine whether we are in toppling inside, balanced or toppling out of the turn.
The top part of the upper body has quite a bit of heavy stuff - arms, shoulders, chest, head - and angulating moves that amount of mass above the 'original' balance line. Whilst the hips may indeed move below the balance line, the top part is further from the pivot point and hence able to exert a greater moment.
My understanding and experience is that we control the relative movement of mass wrt the balance line through the amount of separation and the amount of flex at the hips in order to control our lateral movement into and out of the turn. This relates more to longer turns (such as Batz above - blue outfit skiing in post #10).
Am I missing something here?