You can certainly ski the zipper line using PMTS movements, but the result is going to be somewhat different due to the shape of the bumps exerting outside influence on the ski. Typically, what will happen is that you will get engagement at the top of the turn and a quick carve, but in the confines of the bump, you can't finish the turn. Instead you will contact the low face of the oncoming bump early in the bottom half of the turn and you will have to quickly flex to absorb it. While flexing, you release, pull back and tip into the new turn. You have to get some speed control by dropping the tips into the trough as you pass over the bump and absorbing the hit of the oncoming bump with aggressive flexing. Most of the bend of the skis is vertical, rather than horizontal. Like the dewdman says, all movements apply. To ski the zipper effectively, you will need all of the essentials working at a high level.
Competitive bump skiers aren't taught to ski the same way we approach skiing, but there has always been a distinction between those who carve and those who don't. Of those competitive bump skiers that do carve, most are big-toe dominant and there is some leg steering/knee drive involved as well. Competition skis are effectively straight skis and you can't just put them on edge and expect them to turn. All SkierSyn is pointing out is that competitive bump skiing has its own technique that works especially well on manufactured bumps. He is not saying that PMTS technique cannot be used to ski the zipper line; there are plenty of skiers (including myself) who use PMTS movements to ski that line.
That said, the zipper line often isn't my first choice as it requires more work than I am usually willing to do. The pace and range of movement is extremely high. Skiing the tops of the bumps is usually smoother and requires less effort.