Actually, there are two types of wedge turns and wedge christies. Each can be done by any skier, regardless of proficiency. They are the braking wedge and the gliding wedge. The difference is the intent of the turn. The braking wedge results from a defensive mindset. The intent is not to go somewhere, but to use the skis as brakes (the same intent used by most skiers in all terrain). The skis are pushed against the snow to slow down. Any actual turning movements are incidental. The gliding wedge is the one performed at exams and the maneuver taught by good instructors to beginning skiers. It incorporates all the movements of any high-level turn, including a dynamic parallel turn. The difference is in the intent, which is to go somewhere. Gravity starts the turn, helps shape it, and the turn ends when the tips are steered uphill to let gravity slow you down. This allows you to maintain the speed you want without thinking of braking (a very different intent from the braking wedge). When Bob Barnes was coaching me to do an efficient gliding wedge christie, his instruction was very simple: "Try to make the best basic parallel turn you can, but do it at the slowest speed possible." By reducing the radius of the turn, actively turning the tips uphill to maintain the desired slow speed, and performing the maneuver on the gentle green terrain where it would be performed by a novice skier, a wedge develops naturally. By the way, the Austrian ski team often starts its training day by performing wedge turns and wedge christies. The accuracy and precision required to do those low-level maneuvers is then translated to their racing turns. The same intent and movement patterns are incorporated.
Here are some demos of the gliding wedge and wedge christie. Even some of these high-level demonstrators have a problem with making them totally accurate. See if you can see a difference between demonstrators!
Edited by mike_m - 5/25/15 at 10:00am