Originally Posted by The Joker
That's not a retcon. The chemical bath origin was ALWAYS part of his origin. That comic is the first time the concept was introduced. It's who he was before it that is the difference in origin.
It was some kind of a retcon. A gangster called The Red Hood or a harmless comedian who had to wear the red hood because of some unfortunate circumstances is a difference. I prefer TKJ's origin, though. And I love Joker's line about his past as "multiple choice". A Joker WITHOUT a certain origin is so much more intimidating IMHO.