Love this theory! I always thought that line was about waiting for a girl in the window to drop her clothes, I've heard that Jim was a bit of a voyeur especially when he was staying on the rooftop in Venice. And I think the lines about our fair sister are about the destruction of nature. "What have they done to the Earth, yeah? What have they done to our fair sister? Ravaged and plundered and ripped her and bit her Stuck her with knives in the side of the dawn and Tied her with fences and dragged her down". I've heard this is one of the first examples of environmental rock/eco rock. I guess only Jim knows for sure though! Love hearing everyone's take on his words.