It was on perhaps my second reading that I realized what a wonderful chapter this was and it has since been one on my favorite conversations. I think this is so because as you said, it is unexpected and makes one realize that Mr. Knightley's visits over the many years to the Woodhouses evolved into a very special friendship with Miss Taylor/Weston as well as Emma and her father. I can picture Emma, Miss Taylor and Mr. Knightley having many warm, comfortable conversations as Emma got older and enjoying each other's society. I imagine a great deal of smiles and laughter as they all three seem well-suited to this sort of smart conversation and jest edged with understated humor.

Yes, I am always amazed anew at the things Mr. Knightley can say to her which only someone on a familiar easy-going footing would be able to do without offending. It is obvious in this conversation that this type of banter is something that they have indulged in over the years. And I too love this humorous side of Mr. Knightley that we can harken back to as we go through the story.