Can I just reiterate how much I love the fact that Holmes used an exclamation point after Watson’s name? He always sounds so excited when he says the name (Vhatson!), and now he’s excited just to write it. He has a friend and a partner and his name is Watson! and he appreciates that so much.
Also, I appreciate the fact that the Russian producers could easily have written this letter in Russian for their audience, yet opted in all their printed language to stick with English, to help the audience better place themselves and the stories in Britain.