Originally Posted by The Joker
Your 5 year timeline is false.
Haha. Of course its false. Its fiction. There is no timeline. Using any timeline at all is an exercise in retroactively choosing which continuity errors to ignore to try to fit it together in a way that makes sense.
You ignore the kids ages. You ignore the ridiculously short duration of use of the first batsuit. You ignore the absurdity of super-ninja Bruce Wayne acquiring a chronic injury in a year. Or the absurdity of cleaning up a corrupt-to-the-core city and retiring that fast. Or that Ras had no time to train, use and exile Bane between Bruce leaving him for dead the first time (in the Himalayas) and Bruce leaving him for dead the second time (on the train).
All because the Joker said "a year ago these cops and lawyers wouldn't dare cross any of you", which you interpret to coincide with Batman's first appearance.
For what its worth ... I said a 3-year gap between BB and TDK. On my timeline, the events of Begins took 2-years from his initial return to Gotham to the League of Shadows attack. 2-years for BB + 3-years between BB & TDK = 5-years total service time by the time he retires.
So, the Joker would've been operating as a small-time criminal for 2 or 3-years between BB and TDK ... not 5. He didn't start at the same time as Batman. Sounds fine to me.