His deductive skills are being made to look inferior so that Watson looks useful and important in this adaption. Watson seems to best him most of the time at deduction, which is a cool thing, but I hope in the future Sherlock gets emotionally better and stronger and his deduction skills improve. Right now he is still suffering with dealing with sobriety, he's not focused, I guess that's one side of it and then the other is to make this Sherlock imperfect, broken, and normal. Which to some can seem a disservice to the canon-Sherlock of past adaptions but it makes this Sherlock so flexible and emotional. Which is refreshing.