>>82172601I don't know about the status quo but I really think that in the moment if Batman has the option to say, watch the Joker lose his grip and fall off a cliff, vs. getting him up and taking him to Arkham, he would always choose Arkham. I see it as less of some self-enforced moral rule or because he secretly likes the Joker or something like that, he just can't help himself and he'll probably think back to this moment where he let the Joker die whenever he fails to save someone. "Was it really that it couldn't be helped or did I let it happen?" Maybe a post-deadJoker setting could be a premise for a story where Batman let the Joker die even though he could've saved him.
But back to the Joker, he'll totally regret it the moment he catches the Joker but he's not going to shove him back off the cliff so he takes him back to Arkham, and drinks himself to sleep or something. Maybe beat him up a bit so that he'll shut up on the way there.
There was a similar occasion in a The Question storytime a couple days ago. Some punks dropped a guy off a building to spite Vic who told them not to drop the poor guy. "If you drop him, you'll soon follow". After beating them up, one goes over the edge. The guy spends several pages begging for his life and how Vic should save him and Vic was like "No, I warned you." Guy finally slips off and Vic grabs him last second and beats him up a bit more and spends a couple pages bitching about it to Tot, his old guy mentor dude. Bruce and Vic aren't the same but I could definitely see a similar situation playing out every time a villian is on the brink of death and Batman is staring down at them deciding whether he should save their life or not.