Well then its lucky he appeared this way because I have quotes in which Jonah and Chris say they didnt touch upon on him being detective because it wouldve been too much.
Well, maybe you should post up the quotes, because he did do detective work in BB, he sat and researched all the cops, judges and folk from the DA's office, which led him to Gordon, which led him to the docks, and Flass, who he got the info from which led him to the narrows and the Scarecrow. After he was defeated by SC, he followed Rachel to AA, listened in on the conversation, which then led him to interrogate SC, who told him Ras Al Ghul was coming.
Detective work is sometiems as basic as that, follow leads, get the facts, interrogate suspects...he may not have been portrayed as the world's greatest there, but it was still detective work.
I am guessing Nolan and co said something along the lines of not focusing on him as being a detective, along the lines of a Sherlock holmes movie(an old one).
My personal take is that it make the character more real and easier to be identified with - if hes like perfect in everything that doesnt make him much real. If he still has emotional problems and needs help of other specialist in certain areas, that makes him more real, more human
The thing is, he needs to be v smart in order to survive on the streets, he has to think on his feet in dangerous situations all the time, you can put on the muscle and learn all the karate movies in the world, but if you are not smart enough, you will make the wrong move and it will all be over in a gunflash/jailcell.
So, it stands to reason that this same ability to weigh up the situation, on the streets, would also apply to weighing up the facts of the matter when it came to long term detective work, it is the same principles at work, instincts about people, noticing patterns and methods of operation, gut instinct, connecting the dots...and so on.
You can't have a Batman who is smart on the streets, but not as smart when playing Cluedo, if he can survive on the streets for years and years as a vigilante on his own, then those instincts will automatically be there for him when he sits down to the facts of a case.
Yeah, he should be the world's greatest detective, damn right, lol, for that reason, it's the same skillset he uses on the streets.