...by timing issues. It was the main thing I noticed the first time I watched.
In "A Scandal in Bohemia" Irene Adler bests Holmes. That's why he held her in such regard. I was disappointed that Sherlock came out on top in Belgravia. Not only that, she apparently needed help from Jimmy to get as far as she did. Very disappointing. How can she be "The Woman" if she can't best Holmes. The whole point about Bohemia is that Holmes is not infallible.
Apparently, I'm not the only one who noticed.
I had the same reaction the the first Robert Downey, Jr., Holmes movie, wherein Adler is similarly Moriarty's errand girl*.
* Watson's new ex-girl friend was played by Oona Chaplin, granddaughter of Charlie, who was portrayed on screen by Downey. Coincidence?