hm....as far as I know, only two extreme kinds of skiers need pole planting for turning.
All intermediates only do pole-planting because they are asked to do so. pole planting is all cosmetic for intermediate skiers.
1) high hands
they use pole planting to time the turn
2) absolute beginners
sometimes they use pole planting to turn/stop because they are out of control and the skis refuse to turn/stop:-)