The big question at hand seems to be whether or not Keller could be a rhetorical theorist. Bluntly, the answer is no; if there is anything that this unit has so far imparted it's that qualifications, screens, titles, are the somethings that the beholder must decide for him/herself even though it may seem to be given to us by an outside party. Thus, despite labeling (in the case of George the most common kind that occurs post-work-post-mortem), Keller could only logically be a rhetorical theorist if she herself had donned that mantle using her own signs.
That being said, I do agree with how George demonstrates a case for re-classifying Keller's writings/actions for the purpose of Rhetorical Theory. Part of this reasoning comes from George's comparison of Keller's work to Burke's consubstantiation, where you can "'persuade a man only insofar as you can talk his language'" (George 342). There is no doubt that Keller could consubtantiate. The very fact that she was so celebrated relied on her ability to overcome the obstacle of communication despite her disabilities. Even if one were to argue that she could not properly hold a conversation, or listen to language, she still had written language, which is nothing but a transcription of spoken word, and therefore still sufficient to offer a position in the community of language.
I will note that before this time, this learning process pre-dating her knowledge of signs, I'm not sure what method was used or how she got to a point of understanding, but it might shed light on what kind of consubstantiation Keller arrived at. Briefly, and using De Certeau's model of the city, it would seem that her viewpoint is always that of the "aerial view." For Burke, participation in the "city" might have translated to a route that could be characterized by a 3 step process to "enlightment" or awareness of the governing power of a system of signs: 1) immersion by "cultural piety" (George 341) 2) removal by Burkean "translation" (George 342) which would free a subject from said "cultural piety" (leading to the "aerial view" of De Certeau's city) and 3) re-immersion with the new purpose and ability to affect change through an objective/relative knowledge of a sign system as malleable; a unit for appropriation.
Yet for Keller, with consideration to her physical condition and her own words "'We cannot be free until we know the nature of our bondage and examine the chains that bind us'" (George 341), it is my wish to propose that her "participation" or consubstantion was limited, started with, and ended, exclusively and entirely in step 2 of the above model. It seems that Keller's route was static, moreover, her origin never being that of rooted in any widely used symbolic system, but once learned, started with the "aerial view" and never came down; can't come down.
This doesn't de-value her insight, or her skill as a writer, it simply gives her an outside looks at why other people to her are "blind" and "deaf" which would otherwise be impossible if one did not separate him/herself from his/her symbolic system. She infinitely plays the important role of the chorus.
With Keller being eternally relegated to the "aerial view" of DeCerteau's city, and with support from George, it would seem that what Keller could justify, perhaps even has lived as proof, is a an epistemiological notion that signs are equal experience to that of the senses.
To borrow from Keller:
"Of course, I am not always on the spot when things happen, nor are you. I did not witness the dreadful accident at Stamford the other day, nor did, nor did most people in the United States. But that did not prevent me, anymore than it prevented you, from knowing about it" ("A New Light" 95).
Keller even argues that texts are the "eye and the ear of the world" (George 346), giving, a symbolic system a physical strength and quality equal to that of the human body. By relation, if Keller's symbolic system was designed to interpret another symbolic system, which in turn referred to sensory perceptions, it no longer becomes a question concerning equality of meaning, but a recognition that degrees of separation from the "norm" reflects an old cultural stigma to "devalue" the "other." That no matter how much work is put into understanding, and how accurate a translation is, a place in community, and more specifically language, is something innate to those with an origin within a given system.