Look into the Bates method, it's natural vision research from an ophthalmologist in the 20s. The argument is that animals (including us) naturally move neck and eyes in exactly tiny little movements literally all the time, non-stop. And that is healthy because constant movement promotes relaxation, whereas keeping your neck (and eyes) fixed leads to tension and over time is what actually increases our prescription, which he argues is just like being inflexible (that is, it becomes your new normal), but in the eye and neck muscles.

So I'm actually pretty excited for something that needs me to look around all the time. I've still gotta try making my text editor twitch about all the time. A moving target makes more sense for our predator eyes, so maybe VR will finally allow people who work with computers not to have disproportionally more need for glasses.

Wouldn't it be the exact same as outside the Rift, assuming the head tracking is implemented correctly? Outside the Rift, movement changes perspective. Similarly so inside the Rift.