I think most have been said in this thread now, I'll just add some basic physics.
Releasing forces does not eject or project you in any way. When you release the forces you just keep going in whatever direction you were going. That is why you need to have started the CoM upwards movement before you retract. Eventually gravity will take over and get you down again.
There is very little energy stored in a bent ski. I can bend a ski the same amount with one hand, it is not enough to cause float or rebound.
The following may not be basic but it is important to understand if you want to understand how skiing works:
The forces on the skis have a component perpendicular to the surface and a component tangent to the surface. The tangent component is always there if you are turning and it is what makes the turn. The perpendicular component affects the relative height of the CoM and it is also necessary to get grip. The perpendicular component is on average proportional to your weight. The only thing you can do is distribute the force differently in the turn. If this component is high when the skis are not on high edge you are wasting it. If it is high in the apex you get good grip. If your CoM is on a constant distance to the surface the perpendicular force is constant. This does not work outside of good conditions/easy terrain and it will never allow you to reach high angles. This type of skiing is also done be flexing in transition, but it should not be confused with the reasons that racers flex.
In summary CoM up and down is good, but not if you create it artificially.
Edit: One example when this is applicable is ice. Many skiers tense up and have more pressure in transition when they ski ice, but what you really need is agressive retraction that minimizes the pressure in transition. That will give you ice grip.
Edited by Jamt - 1/30/13 at 12:42am