It's an important clarification, not because the Golden Rule requires modification, but because we are such radically self-centered critters that we can misinterpret even such a seemingly simple thing.   What you're saying is implicit in the rule.  Presumably, we want others to take our perspectives and our feelings into consideration when they do unto us.  That requires them to get to know us a little bit.  It's that relationship-building that makes the love ethic so radically healing and transformative.

I think you may be shortchanging empathy here, though.  If you've bothered to get to know someone...particularly someone who is radically different...then you gather awareness of their inner life.  It's not complete, but neither is it just empty imagining.

It would be interesting to read your thoughts on the moral ambiguity you seem to be expressing here.  Is there no "right way?"  Are all differences equally valid?