I think anytime a skier tips from the LTE to the BTE there has to be rotation as the knee rolls down hill to engage the new edges, I don't it is consistently possible using the ankle alone to make turns tighter than the skis spec'd radius.
Again, where do you want to go and what do you want to do.
FWIW, at the turn finish of the QCT I drive my inside foot down, onto my heel and forward 4" - 6" to super load the edges to tighten the turn while simultaneously pole planting. This harness's enough energy to propel me weightlessly across the fall line as I retract and instantly open my ankle and roll my foot onto the BTE to engage the new shovel edge.
During retraction the old down hill ski will also be weightlessly rolled onto the LTE but will be retracted slightly further than the old uphill ski creating the "mysterious" move, or a mini telemark turn if you will. This is where the range comes from to slowly drive the inside ski forward during the bottom 1/2 of the turn and abruptly at the turn finish.
I'll engage and ride the shovel edges weightlessly through the top 1/3 of the turn with very little tail pressure if any, this creates the feather at the top of the turn.
A good drill to practice tightening up your turn is to hang on the edge of the steepest groomed you can find and do the 1-2-cha-cha-cha. Tighten your turns during the cha-cha-cha using your poles plants to increase the cadence until you can link 6/9/12 super tight turns in a row, use the 1-2 to relax/ regroup and recenter yourself for the next series.