I am not sure that I understand the last few contributions on this thread.
If I make a VC, then whatever Lightroom adjustments I had made to the original will be carried over to the VC. If I don't want them, it is a single click to revert the VC back to the original import sate. From then on, neither processing the VC nor further processing the original causes one to affect the other. One of the great benefits of LR is that I can have dozens of different VCs of the same image, all processed differently and independent of each other. And, throughout, my Raw file remains totally unaltered.
Going back to the original question, as soon as you import an image into LR, it becomes "touched" by whatever default (or selected) import preset you are using. Therefore, all my images that were imported in LR1, 2 or 3 show their original state until I decide to convert them for processing in LR4.
And, of course, one of the benefits of the way that Lightroom has improved with each successive version is that images that were not thought worth bothering about in earlier versions suddenly present possibilities in the latest version.