I spent quite some time this afternoon mulling over this section. Then I read it again, and, rather boringly, came to the conclusion that Catherine's embarassment had nothing to do with the significance of "loving a rose" (although I am still totally delighted with the theory) and all to do with the confusion people sometimes feel when put on the spot to answer a wholly unexpected question.

What I mean is this. She is quite frequently awed in a pleasant way by Henry's intelligence and conversational skills. This, compounded by the fact that she has just berated herself for being silly about the cabinet and terrified that Henry might find out what she was up to during the night, makes her naturally nervous of either giving herself away or saying something that will demonstrate her ignorance. JA writes: "Heaven forbid that Henry Tilney should ever know her folly!"

I don't know why, but when I reread the passage, I couldn't detect any signs of Henry dropping romantic hints. I found no more than his usual easy banter.

I think this is what it is all about...as dull a theory as it might be.