It's kind of hard to realistically critique a movie about a man that dresses up in a bat costume and fights crime as being too far fetched or unrealistic.
Some of it is suspension of disbelief (Shoot if Phoenix Jones exists in real life, I'll allow for Batman to exist in a movie), but sometimes you have to wonder. For example: 1. The stock exchange bankruptcy. Guys break into the stock exchange with Waynes fingerprints and bankrupt him. Put that in front of any judge and that'll be reversed in minutes. He might not get his money back instantly, but c'mon. Seriously. 2. There is a TV with cable and electricity in the prison pit. Let the logistics of that sink in. 3. Bruce is thrown into this prison pit without his magic leg brace (remember how he had no cartilage in his knee?) and climbs out... What? 4. Every cop in the city goes into the sewer at the same time because I don't know why (911 calls, what are those?). Why not call in the Army, Marines, etc.? 5. The end explosion. Oh lawd don't even get me started there because there is too many ways that this is a problem. Lets just say there won't be a fourth movie because everyone in Gotham got cancer from radiation and died, and leave it at that. Those are just the glaring problems.
Those are all valid points, for sure. The last one, about the explosion is one that I thought about while watching it. All the others I was able to suspend belief for. I didn't consider this one:
Bruce is thrown into this prison pit without his magic leg brace (remember how he had no cartilage in his knee?) and climbs out... What?
That's a good observation. Perhaps it was a rehabilitation brace?
Oh you have no idea: http://www.aaronsw.com/weblog/tdkr
The film begins by asking: what happens if conservative law-and-order policies actually worked? The answer, we quickly learn, is that it destroys the people behind them. Without anything to fight, Bruce Wayne is just a reclusive withered husk, while Commissioner Gordon is actually going to be fired. Given that these are two of the film’s most sympathetic characters, we naturally tend to deplore this situation. And so the film’s first key point: the champions of law-and-order do not truly want to succeed at their stated mission.
I think they are in ruin because you can't build a house on a foundation of lies. Obviously Comish Gordon is struggling with the lies he told in order to preserve the memory of Dent and build legislation on the back this lie. -This taints the peace. I think that is the theme here.