I'm not "just waving my hand" and saying it doesn't exist. But the fact is over analysis is more often ascribed to HS English Teachers than ADD is over proscribed.
What I don't get is why you think these people didn't use symbolism. Even if they're writing for the masses. Isn't that what Shakespeare did? (answer, yes. He wrote plays so any idiot with a penny could come in and throw vegetables at the audience). The symbolism in his plays is so strong that you'd have to be retarded, deaf, and blind to not notice it. Teachers point these symbols out so you'll learn to see them. Of course they're heavy handed, especially at first. But if they're not, the kids are likely not to notice. And no, I've never had a teacher tell me that it HAS TO BE that way. But I have heard a lot of students without a single idea in their vacuous skulls tell me that the teacher is bad because he'll only accept a regurgitation that he gave originally. These student, on the other hand, don't really have any other interpretation, so apparently they're just built to whine.
Studying only the structure of the grammar defeats the purpose of studying literature. Sure the grammar is part of it, but that's going to leave us without an understanding of what's happening there. A work of literature is a work of aesthetic production, and as such uses symbols, allusion, and other devices. They're there. Ignoring their presence (and as a side note, I want you to enjoy both my alliteration and use of all homonyms of "there" in the last two sentences) is foolish and willfully ignorant. No one has said you can't have a different interpretation. But if you refuse to see that the red rock is a potential symbol, than it's you, not the teacher who has a problem. You can ignore it as not meaningful once you've explored it's potential significance, but if you ignore it before than, well, who's doing the "hand waving" now? Goldman's language calls our attention to the color for a reason. Why is it such a problem if a teacher calls your attention to it and gives you a potential meaning?
I obviously had a different school experience. No, I wasn't seriously challenged by my standard English classes in high school, but that's because frankly, I'm much smarter than the average bear. Many people were challenged. I did take literature classes for electives that did challenge me, however. You're making generalizations about an educational system that a) you didn't graduate from, even though you did spend some time in it, and that b) has been consistantly rated as one of the 10 best in the country. FCPS is a MUCH better system by nearly ANY reckoning than you're making out to be. Yes, I had some bad teachers, but not a single one of those was due to over-analysis or forcing me to think like they do. without an exception, every bad teacher I had in public school was due to the teacher not explaining what the expectations were.
Remember that in public school you are, by and large, dealing with students who, for whatever reason, do not have the sophistication to do a solid analysis of a book. Yes, there are exceptions, but you can't educate your public by building your core system by the exceptional cases. You have to build it on the general level of understanding. You introduce them sometimes by giving an extreme version, which they (the students) are obviously going to tone down when they put it into practice. So in the few cases of overanalysis, it still serves a purpose, and I'm not convinced that the damage you say it is doing is even remotely the case.