@Lieutenant Dan - I grew up open water skiing and my dad told me the goal was to see how close I could get my shoulder to the water. Obviously that isn't constructive in the slalom course - tons of load, not as much speed (inefficient). It is worth understanding that as a starting point, although not necessary. What I am doing it making a conscious effort to keep my head and shoulder height, or distance off the water, as close to constant as possible through all aspects of the course. So when I go out for my gate, I change the direction of the ski, but don't "load the line" and put my left shoulder down. Instead, I keep my head and shoulders high, and let the ski direction and the boat do the work.
Similarly, when I turn in for the gate, I don't drop and load my right shoulder. I keep my head up and my shoulders level and change direction, again, letting the ski direction and the boat pull do the work of acceleration. By reducing my input against the line, I believe (and people who ski with me would agree) that I can be more efficient at generating speed, maintaining handle control, decelerating and turning. Everything is faster and better.
Not to be too long-winded, but a couple anecdotes. One, @Chet told me the first time I skied with him. "Why are you trying so hard to make your ski go after the turn? You can't make your ski go, only the boat can make your ski go. Stay on top of your ski, and use the power of the boat." Simple, true, and still required a lot of work for me to break my old habit of turning, loading, and going. I am far quicker ball to ball doing it Chet's way than my old way.
Second - watch video of the top skiers. While they may "load the line" at the maximum resistance point across the course, look at how far off the water their head and shoulders are, AND look at how little that height changes from lean, to glide, to pre-turn, to turn, to lean again. They are generating load -- the right load at the right place. But they are not "dropping the hammer" with their upper body/head and shoulders.
So - what I mean is that the more I work at maintaining a more consistent and upright/off the water head and shoulder position, the easier my passes become.