First of all, pole planting is certainly useful. But when used improperly, it can be harmful.

I think the situation where pole planting is not needed is when you’re skiing purely in a carving style. The so-called pure carving means there is no snowplowing at all, turning entirely based on the ski’s own turning radius, relying solely on gravity and the centripetal force provided by the snow surface to complete the turn. In this case, the only friction is along the longitudinal direction of the ski (overcome by gravity), making it a style of skiing that requires no extra effort, and thus, no need to rely on any force from your hands. It’s also the smoothest way to ski.

Of course, this is a rather ideal situation. The reality is: you’re always mixing snowplowing with carving. When you think you’re carving, you’re actually just carving a lot more than snowplowing. But once you start snowplowing, in addition to gravity, centripetal force, centrifugal force, and longitudinal friction, you also introduce a lateral friction force along the ski. At this point, the overall force dynamics become less pure. And when the forces aren’t pure, your effort isn’t pure either. So in this case, you might need pole planting to help generate some force.

Overall, my understanding is: completely pure carving doesn’t require pole planting at all, nor can you plant poles effectively (you can lightly touch them but shouldn’t put weight on them, because any downward force from your hands becomes resistance rather than assistance, affecting the smoothness of your run). This is an ideal scenario, which generally only occurs at higher speeds where there’s enough centrifugal force to maintain edge angle throughout the turn, approaching the ideal case.

More often in real situations, you’re only carving 70% or 80% of the time, so you might need to use pole planting to help generate a bit of force. The purer your carving, the less you’ll need to rely on pole planting for assistance, eventually just lightly touching the poles. The more you snowplow, the less you carve, the more you’ll need to draw force from the poles, and the more essential you’ll find pole planting.

The above discussion has been focused on carving, but skiing isn’t limited to just carving. It’s just that on groomed slopes with appropriate gradients, carving may be the most exhilarating and enjoyable way to ski.

When you’re not carving, I believe pole planting is a very fundamental skill. Because it’s quite likely that if you can’t get proper assistance from your hands, you might end up twisting your body and generating force from other improper areas.

The above are all my personal opinions. Please forgive any inaccuracies, and I welcome corrections.

Below is also a discussion on “accelerated turning,” which is reposted here in the main thread for everyone’s convenience.

Accelerated Turning

Longban: “I agree with the original poster’s analysis.
Pole planting has the effect of aiding accelerated turns. When running straight, making a 90-degree turn is almost impossible—you need to follow a curved path. But if there’s a utility pole ahead, running up to it and grabbing it with your hand allows you to instantly turn 90 degrees and continue running.
In skiing, pole planting can serve as that supporting pivot point, much like the utility pole.”

I have some new thoughts and will continue discussing accelerated turning.
When turning, you can consider the skis and your body as a whole moving in a circular path around the turning center. In other words, we can simplify this issue to a circular motion problem.
Accelerated turning can also be described as achieving a smaller turning radius, or making tighter turns.

The following will discuss this question: Given a fixed speed, how can you achieve a smaller turning radius?
From the principles of mechanics, a simple answer is: generate greater centripetal force. So, how do you get greater centripetal force? When carving, the method to achieve greater centripetal force should be to apply more force while edging and pressing down on the skis. Pressing down on the skis has two effects:
One is gaining greater reactive force from the snow surface—the reaction force the snow gives to the skis is the centripetal force, and the rebound force from the flexed ski to your foot is also centripetal force. The harder you press, the greater the reactive force (i.e., centripetal force), and the smaller the turning radius.
The second is that as the ski flexes, the shape change of the ski itself results in a smaller turning radius.

From the above analysis, it’s clear that the stronger your legs are, and the better you can use that strength, the tighter carved turns you can make.
But that doesn’t mean the harder you press, the smaller the turn radius can become infinitely. Ski shape, the skier, and the snow surface all have their limits.

So how do you make even tighter turns? Let’s look at the issue from the perspective of increasing centripetal force. Effective pole planting, using the pole as a pivot, can transmit an additional centripetal force to your body through your arms.

From this perspective, pole planting is a last resort—a final measure—when the maximum effort from your feet still isn’t enough.

Skiing is primarily about foot movement. When your feet aren’t enough, you have to use your hands.