Some brief searching suggests it’s Don’t Know i.e., the way cartoon characters are often immune to danger because they’re oblivious to it.
My personal fanwank that I’ve posted about before is that Batman and the other “suits” who have no metahuman abilities nonetheless possess something I call “super competency”. That is, anything they’re determined to learn to do they can do at the top .0000001 percentile of the human species. And multiple skills at that level to boot. That Batman, or even Nightwing or Catwoman operate at a level that, say, ninjas or SOCOM soldiers can never aspire to.
Either makes more sense than my initial assumption of DK, which involves throwing barrels down girder ramps at his enemies.
I know this about Batman, every time he leaves the Batcave he knows exactly what kind of trouble he’s going to run in to because he always has the solution in his belt.