If the Dark Side does feed off of fear and hatred and suffering and all that jazz, encouraging your potential apprentices to murder each other does strengthen whoever ends up on top of the heap. Rather than a bunch of people who can cooperate (which is perhaps a bit too Light Side?) you get one greedy, ambitious, angry, paranoid psychopath who will eventually try to murder you too, which in turn feeds your own fear and hatred and all that. It's a pretty shitty way to run an organization, though.
I mean, I think the whole POINT is to make it not really an "organization" anymore. They don't want an organization because that would necessitate teamwork; they want ultimate individual power with the absolute minimum of cooperation required for continuity of that power.
SWTOR canon Sith Empire actually almost functioned. Like, it was dysfunctional but no more so than the Republic/Jedi of the time.
"Yes, let's take very small children away from their families forever and tell them that feeling things and having people you care about is bad, this will go spectacularly. Wait why are a bunch of these people going rogue and doing scary things, this is completely unexpected but definitely not our fault."
Yep! Take an emotive child and tell them "No! Emoting and having emotions is Bad." enough, eventually they'll hit that angsty defiant teenage phase where fine then, I'll be Bad. You can't control me/don't understand/etc. And then you get Darth Tantrum.
I'm sure we're going to get a lot more backstory about how Darth Tantrum ended up where he is in the next movie, so I'm a little hesitant to draw conclusions that that was necessarily Luke's mistake at this point. Particularly when in the Legends continuity Luke actually had changed some of those aspects of the Jedi Order, like the ban on romantic relationships.
One of the things about pre-Rule of Two is that not only did the Sith become radically different so did the Jedi-the "no children no, emotions bad" thing is very much a product of the galaxy having utterly gone to shit to the point where you had Jedi dynasties running sectors as Jedi Lords and the Jedi had pretty much taken over the role of Supreme Chancellor for life because they needed someone in charge who probably wouldn't get mind controlled. This was a series of devastating wars that took place over the course of a thousand years and nearly destroyed galactic civilization, which got started by a fallen Jedi, so the Jedi were very dedicated to ensuring that nothing like this happened again to the point where they deliberately stripped themselves of most of their power and independence to become largely an esoteric law enforcement arm of the Republic. It might have been less possible for them to so radically restructure the order if the majority of them hadn't been dead due to the Brotherhood of Darkness taking the Army of Light with them with their thought bomb, meaning that the main center of Jedi power remaining was the ones on Coruscant instead of the Jedi Lords.
It seems like there was always, in a practical sense, more than two of them, but that law was set up (to my knowledge) to make only two the REAL Sith and the REAL leaders in order to make everyone else their subordinates. It was as much a power grab as anything, because obviously there will always be more than two users or the dark side and obviously minions are good to have, but if you're the only REAL ones there's no real competition for you. At least, there shouldn't be. And there's a little religious fervency in here, which allows for otherwise weird conclusions to be made with reasons.
@keltena your post made me chuckle but being the pedant I am I actually have an answer of one of your brother's questions. Dead. Literally dead. Darth Bane went out of his way to murder them all because he wanted him and his apprentice to be the Only True Sith. Darth Plagueis mentions that he was in fact haunted by the force ghosts of furious dead Sith and the consciousnesses they left in temples and artifacts and that it was part of the reason he was so bonkers.
I'm just going to keep replying to this thread until actually stopped. That sounds fascinating and I'm going to try to pinpoint who it was. So far, I've found this baffling thing: http://starwars.wikia.com/wiki/Light_Sith But yeah, in my experience, you can 'fall to' anything you have been expressly told can never be yours to have. ETA: def this guy. I'm reading the right novel for weird Sith lore.
"Darth Gravid"? That's almost as... interesting a name as "Darth Millennial" (who presumably fell to the Dark Side through the corruptive influence of smartphone selfies). Or George Lucas's proposal to name Starkiller "Darth Icky."
Maybe this guy? Also is it just me or does his name evoke more "pregnant" than "important"? EDIT: Ninja'd!
You really have to ignore names when it comes to star wars. The names are the worst part. Just pretend they didn't google translate dark-sounding words into weird languages and move on. ...Plagueis's master was Darth Tenebrous. It hurts me. They expect that I don't know the context and just think it's a cool sounding space name. aaaaaaaaaaaaaaaaaaaaaaaaa. ETA: Thinking about it further, I remembered that Sith generally name theirselves and/or are named by their masters, and usually start with a better, more keysmash alien names. In other words, Sith make up terrible names for themselves, canonically, in a manner recognizably different from all other alien naming schemes. In respect to this tradition, when I become a Sith Lord, I will go whole fucking hog and dub myself something like Darth Straight Up Murder to be the most obnoxiously sith Sith there is.
link has big spoilers for the new movie, but i wanted to show y'all what prozd voices (aka the guy who does a great goofy impression) just posted: http://prozdvoices.tumblr.com/post/139745664680/approximately-one-billion-people-asked-for-this i couldn't decide whether to laugh or cry.
IIRC, there's already some extended material that says that Snoke was getting mindfingers into this kid from an early age. Dibs on Darth Infinity-Between-Stars. (Tenebrous is a great name but I can't help but imagine him as the Sith version of Tenebrae from Tales of Symphonia 2.)
Dibs respected. I mean, though, if we get four of us, we can take @Aviari 's suggestion and actually be Darth Cheerleader, Darth What's Her Face, Darth So-and-So, and Darth The Ugly One, which is funnier by the minute to me.
I hereby solemnly swear that if I ever fall to the Dark Side and become a Sith, I will take the title Darth Curtains-Drawn-in-the-Basement, only in French or something so it'll sound cooler.