Bolter and Grusin bring up some interesting points: what constitutes reality in a virtual reality?
Although not distinctly asked, I feel much of their discussion is centered around this question. In other words, they explore the various mediums through which we alter perception. An interesting distinction is made between telepresence and virtual reality. In virtual reality, all is constructed. The visual environment is entirely created, thus all facets of virtual reality are reliant upon reference to ground us in reality. That is to say, any portion of a created digital world needs to contain some references to the physical world to maintain a sense of the real, "If virtual reality is stepping through the medium into unmediated reality, then why does the virtual reality need computers?" (216). In the case of telepresence however, the viewer is more solidly based in the physical world (the virtual aspects of telepresence only compliment the real, rather than dominate/deconstruct it).
Bolter and Grusin define telepresence as a more operational augmentation of reality, "the interface of a telepresence is highly mediated and yet is supposed to be transparent, in the sense that it should transmit a view to the human operator and allow the operator to interact 'naturally' with what she sees" (215). Hypothetically, the function of telepresence is naturally to distort reality, to add virtual features to the physical world in order to strengthen or enhance some cause (like the radiation robot or the surgeon's microscopic tools). In contrast, the function of virtual reality is more geared at creating some form of reality out of distortion, making an environment that users feel comfortable with, or at the very least, understand how to use.
In my opinion, telepresence creates a more real version of virtual reality, and for that reason, is a preferable system. One of the dangers of the digital world is that it often denies reality, or creates a reality so far from the physical world we become accustomed to an entirely different set of standards. If you are presented with starving children on tv..man people change the channel, unaffected. Yet, if someone's internet stops working, immediate anger and panic ensues. In order to be more solidly grounded a constant check on reality is needed. In this sense, telepresence still affords us that option (it only enhances the real for a greater purpose), and is thus, functions more for our benefit. Thoughts?