Alright, just a word of warning: I like to rant about these kinds of things, and when I rant i don't give a damn if my paragraphing is correct and I will unintentionally digress from the main point from time to time. Also, this can be quite boring.

You have been warned.

Back when Sir Arthur Conan Doyle wrote about the famous adventures of the Consulting Detective Sherlock Holmes and his companion Dr. James Watson (A Study in Scarlet first published in the Beeton's Chirstmas Annual 1887), it was written in the perspective of the discharged army doctor James Watson, chronicling the singular exploits and adventure of Mr. Sherlock Holmes. Its general idea was simple, but brilliant: Sherlock Holmes is a consulting detective, someone the police looks for when they're out of their depths ("Which is always," Says BBC Sherlock), he looks at ordinary people and things, the dirt, the windowsills, and from the minute and trifling details he forms a conclusion based on his deductions which is based from evidence, observation, and his vast encyclopedic knowledge. With this, he solves crimes that people might claim impossible.
Conan Doyle couldn't have believed that this fictional detective would gain popularity, so much that Sherlock Holmes would overshadow his creator. He would later come to hate his creation, and eventually, kill him off in His last Bow.

Over the years, there has been many, many portrayals of the iconic crime-fighing duo (No, not Batman and Robin) and primarily, Sherlock Holmes:  Basil Rathbone (RIP), Christopher Lee (RIP), Michael Caine, Leonard Nimoy (RIP)  Jeremy Brett (RIP), Robert Downey Jr., Jonny Lee Miller, Benedict Cumberbatch and Ian McKellan, to name a few. And I can honestly say that a majority of us has or is still wishing to be this genius of a man, to wear the deerstalker hat, pretend to smoke a pipe and go around solving crimes with a sidekick, forming deductions which will leave people astounded and mistaking you for a wizard.

Well yes, enough digressions. The Classic Conan Doyle way of writing was quite simple, it only took me a few minutes to get a feel of the language when I first read his stories, but the usage of technical terms is different thing entirely. Since Sherlock Holmes is quite knowledgeable in chemistry, anatomy, and sensational literature, it is quite difficult for us ordinary folk to understand what the hell he's saying half of the time! He also knows quite a lot about geology, for example, he knows that that brown smudge on your left trouser leg is mud distinctive in the upper Thames, near White Chappel. That you have been traveling for about a day now and that you carry a small luggage, judging from the color and size of the splash. That's how good he is. But, the thing is, once he makes these deductions from commonplace things, we take him for a fucking wizard. But after he explains us how he formed these deductions, we thump out hands to our foreheads and exclaim "Of course! Why didn't I think of that?" (The common reaction of Watson after Holmes has explained himself)
These things are still existent in the new  BBC television series Sherlock, featuring the talented gentleman Benedict Cumberbatch and Martin Freeman from the Hobbit. Indeed, these deductions are made even more fantastic and sometimes unbelievable. It may simple stem from the fact that the viewers of today have standards that are constantly spiraling upwards, they cannot be content with a elementary cases like the Adventure of the Red-Headed League or the Adventure of the Blue Carbuncle.

But try to write a fan fiction on the BBC's Sherlock, however, it's like making Michael Bay write a movie that doesn't have any explosions in it, it can be done but it's reaaaaaaally difficult, just like if your writing style/mindset is at the moment the 20th century London of the Great Detective: hansom carts, Holmes smoking more tobacco snuff than Wiz Khalifa, Watson being more clueless than usual, more house calls to Holmes than to a doctor, simple plots. Do relatively simple plots and crimes diminish the enjoyability and depth of a story? No. You don't need a complicated plot to give the reader a sense of what you're writing or to give them a laugh.

Furthermore, I couldn't help but notice that a majority of people these days (teenagers, usually) cannot stomach or take to read the original cases, whether they simply don't want to, or because they think they're uncool or lame, probably another reason why the more modern incarnation of the sleuthing detective was created, the movie Sherlock Holmes featuring Robert Downey Jr. and Jude Law,  the BBC's Sherlock which is already mentioned somewhere above, Elementary with Jonny Lee Miller and the female Dr. Watson Lucy Liu among others. The shows and movies of today feature plenty of action, comedy, and romantic interests that are too much for  Grenada's Sherlock Holmes to contend with today.

Anyway. To me, writing in the classic Conan Doyle sort is easier, you can add more things to it that you just can't in fan fictions of Sherlock or Elementary. For one thing, neither of these Holmes smoke a pipe, ride a dog-cart, solve trifling cases such as a bank robbery or a madman smashing Napoleonic busts. And another thing, we have yet to see Benedict Cumberbatch box a drunkard at a tavern, Robert Downey did it, why can't he? Just a trifling thought.

Although it is of no consequence to mention that it is getting increasingly difficult to make fan fiction with the grand flourish and theatricality of  20th century literature, because to some people it is too slow, not enough action and interest. And modern literature (or at least, most YA novels) focus more on what the characters think and on the dialogue, not saying that that's a bad thing, for from it, but the flowery and detailed descriptions of yesteryear's slowly losing its grip on today's readers' minds.

Really, the BBC's Sherlock was more vain, more silly, cute, more disliked by Scotland Yard (as was evident in the Study in Pink, with Anderson and Sally) and eccentric than Conan Doyle's, although we might just be seeing a smaller part of his life because it is a series, *Cough* and there are only 3 seasons with 3 episodes each *cough*.

From what I read and watched, the Victorian Holmes encountered far more difficulty than his modern counterpart, no smartphones, they had to send telegraphs, cabs took longer, money was somewhat easier to counterfeit, accessibility of weapons and drugs (Now you know when to time travel), medical care (not to mention that practically nobody wears a top hat nowadays!). In short, Classic Holmes had to go out and actually solve the cases, because nowadays people don't wear suits everyday everywhere, you wear T-shirts, hoodies, tank-tops, you no don't need to go the library to get information anymore, you just need look it up on Google!
*Sigh* Kids have it easy these days.

UPDATE: 30/06/15

Modern renditions of Holmes (or most adaptations of the past 20 or so years) have been flashier more stunts, more explosions, more adventure and excitement, which the past tales sometimes attempted but due to trying to be as accurate to the books as possible while maintaining the air of dignity, gentlemanliness, and the solemness of Holmes during a case. You can use the Lord of the Rings and the Hobbit movies by Peter Jackson, for example. You will see some key differences between them, the same can be said of Jurassic Park and Jurassic World. It could just be the charm of their compensating for their limitations brought on by their time, such as goofy-looking animatronics or cliche action clips, but there's a certain feeling and wonder in the original renditions, if you get my meaning.