Well, I'm not sure where we agree or don't now. We certainly agree here:

But while I derived nourishment from Rawls Theory of Justice I wouldn't necessarily seek out "classics" of communautarism (or other traditions making a strong case against e.g. gay rights), because I don't feel that dire a need to expose my ideas on moral theories to contradiction. I'd be keen to get that contradiction in smaller and more pre-digested doses.

Yes, yes you should learn about these contradictions of your worldview from summaries of the insights that go against it.

But you also say:

I don't think Robin was saying "read classics in general", so much as "go and spend some quality time with what you'd think is a truly awesome classic". If he had been saying "go and spend time reading classics just because they had the 'classic' label stamped on them" I'd also disagree with him.

But what's the difference? If I'm already so lacking as to need to read (more) classics, how would I even know which classics are worth it? He gives no advice in this respect, and if he did, I wouldn't be so critical. But then it would be an issue about whether people should read this or that book, not about "classics" as such.

Usually when I have identified a topic as really, really important I find it worthwhile to round out my understanding of it by going back to primary or early sources, if only because every later commentator is implicitly referring back to them, even if "between the lines".

Did you regard gay rights as really, really important?