I used to think that the divergence of perspective among readers was a problem for any theory of poetry that stressed its intrinsic value.
Yet now I see that this is a feature, not a bug. We wouldn't expect two great poets to be similar to each other. Part of what we think of as greatness is not being interchangeable with some other writer. So why should two great readers not diverge as much?
If you read Rilke all the time and I have my problems with him, it doesn't mean anything very significant. We are just different readers.
This insight frees me up to write the anti-textbook of poetry without trying to make my reader commit to any particular set of poets.
Am I discovering something that everyone already knew expect me: de gustibus non est disputandum? I think my insight here is a more nuanced one. I still think my tastes are the correct ones, and that I could argue for them, and the you have to defend yours. But there is a space for general principles that doesn't depend on those differences.