I saw the title of what you posted and I was going to say 'oh, you beat me to it', but then I found out you hadn't posted the page I immediately think about when thinking of Batgirl #50 (I hold that it's because Batgirl #50 is made of awesome).
Beyond showing how well Bruce understands Cass, this piece of dialogue is one of my favourite explanations for Batman. "You're crazy." "So they say. But it works."