oscroft, just like any other photographer I don't think you can judge Eggleston's work by this or any other single image, and I personally don't see this as one of his best pieces. All of these photographers have standout single images, including Eggleston, but perhaps he more than the others should be judged on his body of work.
here is a quote from John Szarkowski on eggleston
These pictures are fascinating partly because they contradict our expectations. We have been told so often of the bland, synthetic smoothness of exemplary American life, of its comfortable, vacant insentience, its extruded, stamped, and molded sameness, in a word its irredeemable dullness, that we have come half to believe it, and thus are startled and perhaps exhilarated to see these pictures of prototypically normal types on their familiar ground, grandchildren of Penrod, who seem to live surrounded by spirits, not all of them benign. The suggestible viewer might sense that these are subjects capable not only of the familiar modern vices (self-loathing, adaptability, dissembling, sanctimony, and license), but of the ancient ones (pride, parochial stubbornness, irrationality, selfishness, and lust). This could not be called progress, but it is interesting. Such speculations, however, even if not simple nonsense, presumably relate only to Eggleston's pictures - patterns of random facts in the service of one imagination - not to the real world. A picture is after all only a picture, a concrete kind of fiction, not to be admitted as hard evidence or as the quantifiable data of social scientists
As pictures, however, these seem to me perfect: irreducible surrogates for the experience they pretend to record, visual analogues for the quality of one life, collectively a paradigm of a private view, a view one would have thought ineffable, described here with clarity, fullness, and elegance.