Well that's a really interesting interpretation that only suffers perhaps from being too clever. But then I don't know I'm not qualified to judge. Was the author of John really that subtle? Did he have all these hidden themes going on that you perceive? If he did I wonder if there is evidence the early readers of the book, the church fathers, made those sorts of inferences concerning the blind man's use of language, and even the tense Jesus used in speaking to him. Are you not perhaps mistaking the author of the Gospel of John for James Joyce? I don't know, as I say, I am not qualified to judge since I 1) don't read Greek and 2) am no literary critic. I just wonder.
While the Witnesses, by approaching the 'sacred text' looking for proof texts, may miss out on a lot of the text's richness and complexity, perhaps at the other extreme the ultra liberal approaching the text as a literary critic is in danger of inscribing too much meaning.
Plus whose meaning is it that matters anyway: God who inspired it; the author; the first readers; the redactors who included it in the canon; the church that buit up a tradition around it?
Implicit in your comments above I get the impression you feel it is the intention of the author that is paramount. To a believer however God is perfectly capable of communicating his thoughts through unwitting agents. Many believers resort to that sort of interpretation with at least parts of the Bible, especially prophecy.
Even among "religious atheists" who approach the text as a literary/historical unit rather than as God-inspired may differ on where to place the emphasis in interpreting the text. Is the intention of the author paramount in this text's interpretation? What about those who selected the book for inclusion in the canon and likely penned the 21st chapter? Their interests and concerns seem somewhat different to those found in the preceding document. Yet they have succeeded in integrating the text into a sacred collection, and have evidently made some significant changes along the way. So maybe parsing their agenda for the text is the more urgent task. The document as it originally existed is after all no longer extant. It is only preserved as part of the collection.
I see what you say about the deficiencies in how Jehovah's Witnesses and other proof text-hoarding literalists read the Bible. I can see the advantages of taking into consideration, as you say, the genre of the text, intertextualities and so on. I agree with all that instinctively. I am already won over to that way of thinking. I was a long time ago. I prefer your way to the way JWs do things, I really do...
...but, but, but. On the other hand isn't it also a bit convenient too? Reading the text in the way that you advocate yields a fuller appreciation for the complexity and depth of the text. But I can't help noticing that it also necessarily, and conveniently, results in a reading that emphasizes the ambiguities, outside allusions and internal contradictions, that sit comfortably with your view that the text is not divinely inspired but essentially a human construct to be understood within a literary and historical context, rather than within the context of divine revelation. In other words your method of interpretation confirms your beliefs and your beliefs in turn confirm your methods.
The Witnesses are doing the same when they approach the Bible as divinely inspired, coherent, and filled with proof texts. They start with those assumptions in their reading, and their reading confirms those assumptions.
To be clear again, I prefer your way of reading the text, and I enjoy reading books and commentaries these days that approach the text liberally with a full armoury of text-critical methods. At the same time I know of no objective way of proving that approach to be better, more accurate, or faithful (all loaded words I know) than what Jehovah's Witnesses do. So I would be more cautious perhaps than you are in claiming that the way Jehovah's Witnesses read the text is in some way 'wrong' and that the modern critical approach is 'correct'. All I can say for sure is that they are different and that I prefer one to the other.
