The laws of time and space- and common sense and political reality- are bent this way and that as narrative requires. This isn't proper drama; in real drama the world pushes back against the protagonist- gives him some resistance- but here the opposition is so much wet cardboard- to be punched through with the twitch of a superpower or eluded with a jump cut. There's no real emotion either- just a tacky vein of bromantic sentimentality. Sherlock is an affectless calculating machine except that he wuvs John. Oh God, everything in this universe is so easy.
Conan Doyle was a realist. His Sherlock operates out of the muddy, foggy world of late Victorian London- dealing mostly with small time crime- fraud, thievery, blackmail, domestic murder. His world constrains him. If he needs to get somewhere in a hurry he hails a cab or catches a train. The fate of nations is rarely in the balance. There are no hair's breadth escapes, no ticking bombs. Guns are rarely fired. With the exception of Moriarty- who has an active role in a single story- there are no super villains. Moffat and Gattis are credited with bringing Holmes into the 21st century but that's not at all what they've done; what they've done is translate him to fairyland.