VSP,,, on the reasons for the outside ski ending up on top of the inside ski, consider this. During a right turn both skis are turning right. The skis converge because the outside ski is turning sharper than the inside ski. In essence, the outside ski is converging on (overtaking) the straighter turning inside ski. Because inside tip lead is typically present, the raised/tapered tip of the outside ski will impact the body of the inside ski when they meet, and easily ride right up and over it.
Small radius skis contribute to the problem in that differing edge angle and pressure between the outside and inside skis produce bigger radius differences. The smaller the ski radius, the greater the possibility of convergence. And high inside ski pressure distribution makes directional correction/compensation of the inside ski through a turn more difficult.
Here are some avoidance tactics:
* Tip the inside ski strongly during the transition (period when your finishing one turn and beginning the next)
* Focus on outside foot dominance. The majority of weight should be on the outside foot throughout the turn. This lightens the pressure on the inside foot,, making directional correction easier.
* Keep a rotationally tensioned inside leg. This will force the inside ski into directional correction, keeping it in directional harmony with the carving (turn shape controlling) outside ski.
* You can also do a slight redirection of the inside ski during the transition, prior to engagement of the new turn. By placing the skis in a slight divergent (separating) orientation, the skis can track dissimilar radii, separating as the approach the apex (half way point of the turn) and then converging again from apex to finish. This tactic eliminates the need to continuously redirect the inside ski via inside leg tension through the entire turn.
* If you like high speed arcing (carving), consider getting a larger radius ski. GS skis sport a 21 radius,,, compared to 12 and below in slalom skis and "ANYONE CAN CARVE A TURN" recreational skis. High speeds just contribute to the convergence tendency,,, as the high forces that occur in high speed carving bend the ski even more.
* Practice lateral balance constantly. It will provide you the ability to maintain outside ski dominance throughout the turn,,, make you more aware if you are,,, and provide you the ability to make adjustments when needed.
* Learn to turn on your inside ski. If your skis cross, you'll want to get all your weight on that ski quickly so you can lift your outside ski off it. Standing on both skis and fighting to get them apart is a losing proposition. You'll be going down.
* Finally,,, in the end,,, it's skiing. Flying down the side of a mountain on sticks. You can take all the precautions in the world, but every so often, even to the best of em,, SHAT WILL HAPPEN.