This brought me back to when Case jacks into Molly's mind in Neuromancer. This is again a deeply personalized experience. Slightly different, is that the perspectives are personalized for Case as well as the controller, but there is still a sense of having no control. In the Cave, the person in control could move around and alter the onlookers' experience. There is nothing we, the onlooker in the Cave, can do to take that control back. The same goes for Case and Molly. As much as he would like, he can't even turn the eyes to look around, since she has control of them.
This is profoundly different from most visual experiences I can think of. Driving a car comes to mind. The driver controls the overall setting and motion of the car, but everyone shares in the experience together in a way that each individual can personalize his own experience (look around, etc). I can't think of any experience in my life before the Cave when someone else had so much control of my experience in a visual medium. The closest I can think of is video games, but again every player still gets to personalize his own experience. I think commonplace head-tracking, perhaps through consumer video games, might make this type of experience easier to understand and bear.