I'll take proven veteran movie critics opinion over uhhh ... yours. Bale's performance in The Dark Knight was just as convincing if not more than anyone elses. It was subtle, in a movie that isn't subtle at all. His performance kept the movie balanced. BBC wrote a great article on how Bale's performance is being dramatically overlooked. And let's also not forget that with Batman Begins, it was the first Bat-film that wasn't an ensemble piece, that was firmly about Bruce Wayne's journey, and Bale carried the weight of the entire movie. He is the first actor to don the entire weight of the movie as a character, and it worked because he is the best actor of the bunch, and was the most convincing of the bunch. You wouldn't have TDK and the out of this world ensemble piece that it was without Bale's AMAZING performance in Batman Begins. So when you say "nothing to write home about" ... I take that as you completely and utterly talking out of your ass, or just being ignorant to the fact. He's the best performance from top to bottom, most well rounded character, had the most range in his performances as Bruce Wayne / Batman. There isn't even a comparison to anyone else who took on the role. It would be like comparing a star franchise player who has to carry more weight for a sports team, to a really good role player on a very good team.
And I could give a rat's ass if me and you have problems.